A hacker has leaked 115 GB of Summit Public Schools data containing billions of lines, student and staff…

Justin.sh is reporting on a confidential Cellebrite document that has been leaked to him:

Cellebrite calls it Advanced Unlocks (AU from here on), not to be confused with the “advanced unlocking services” they’ve marketed for years. A press release from earlier this year confirms AU is a new product for 2026.

[…]

According to Cellebrite, AU:

• is a “next-generation AFU vector that is more resilient to Apple’s OS changes”
• works with Stolen Device Protection enabled, which tightens USB restrictions
• is enabled by a dedicated appliance with a stated range (!) of about 8 meters.

AU = Advanced Unlocks, Cellebrite’s term. AFU = after first unlock.

An misconfigured Vibetech database exposed 13.7 million records from previous breaches, including AT&T, Casio and FBI data, passwords and bank details.

A Burnaby School District cyberattack is being investigated after an incident disrupted internal network services and phone lines across the district. The Burnaby School District said the cyber incident came to its attention on Monday, September 21, and that staff are working to contain the incident and restore affected services. The district has not disclosed whether any personal or sensitive information was accessed or stolen. However, the disruption has raised concerns about potential data leaks as the investigation continues.

Burnaby School District Cyberattack Disrupts Operations

According to the district, the incident has affected some systems and operations, including internal network services and phone lines. Staff across Burnaby Schools are working to restore normal operations while limiting the impact on students. The district said the disruption has not affected student learning and that staff are working to ensure schools can continue supporting students. Families, staff, and district partners were contacted earlier in the week about the incident. The district said it will provide additional updates as efforts to contain the incident and restore services continue. The investigation remains ongoing, and the district has not provided further details about the nature of the incident, the suspected attackers, or whether information was compromised. The latest incident follows other school district cyberattacks and cybersecurity incidents that have disrupted education services and raised concerns about the security of student and staff information.

Education Sector Faces Repeated Cybersecurity Incidents

In September, The Cyber Express reported on the Springfield cyberattack, which disrupted school operations shortly after the start of the new academic year. The incident forced schools to close for part of the week and affected services relied on by families, including childcare and school meal programs. The district arranged grab-and-go meals at six locations while the YMCA of Greater Springfield provided full-day care for families enrolled in its programs. Students were expected to return to classrooms the following Monday. The Springfield incident highlighted how a cyberattack against school systems can extend beyond IT operations and affect essential services used by students and families. Earlier in 2026, a separate QLearn cybersecurity incident involving education technology provider Instructure affected educational institutions globally. Queensland Education Minister John-Paul Langbroek confirmed that the Queensland Department of Education had been briefed about the international breach. Early assessments indicated that the incident could affect more than 200 million people and more than 9,000 institutions worldwide.

Education Authority Cyberattack Targeted School Systems

In April 2026, an Education Authority cyberattack investigation found that attackers had gained targeted access to personal information linked to a small number of schools. Authorities identified the incident on April 10 after being alerted to suspicious activity affecting school systems. A forensic investigation later determined that attackers had accessed specific personal information associated with certain schools. The findings added to concerns surrounding cybersecurity risks in the education sector, where school networks can contain sensitive information belonging to students and staff. For the Burnaby School District, the current investigation is focused on containing the incident and restoring affected services. The district has not confirmed any data theft or provided details about possible unauthorized access. As the investigation progresses, further updates are expected from the district on the scope of the incident, affected systems and any potential impact on personal information.

Executive summary

In April 2026, we at Kaspersky’s Global Emergency Response Team (GERT) responded to a security incident at a manufacturing organization in the Middle East. The threat actor obtained domain admin-equivalent control of the organization’s Active Directory environment and authored a malicious Group Policy Object (GPO) named PAYLOAD, linking it at the domain root. Through that single object, the actor delivered ransom notes, hijacked the desktop wallpaper and lock screen, enforced a logon banner, and disabled the local administrator account across every domain-joined Windows workstation — all without dropping a ransomware binary or encrypting any data. The only ransomware we found in this incident was PAYLOAD sample targeting ESXi on Linux servers. Besides that, data exfiltration was observed originating from the file servers and several additional systems, and was later published on the dark web.

This case is an example of two converging trends that define the 2026 ransomware landscape:

1. Living-off-the-land abuse of trusted AD infrastructure. Group Policy is a signed, allowlisted, SYSTEM-privileged distribution channel that the majority of endpoint detection and response tools is designed not to inspect. By delivering impact through GPO rather than through malware, the actor sidestepped the entire file- and process-based detection stack.
2. Encryptionless extortion. Industry telemetry shows extortion-only incidents grow significantly year-on-year. PAYLOAD fits this model; the leverage is operational disruption and the threat of escalation rather than cryptographic denial of data.

We confirmed that no files were encrypted on Windows machines, no malicious binaries were resident on disk, no endpoint persistence was established, and no malicious processes were running at the time of analysis. The entire attack lived inside Active Directory itself. The defensive implication is stark: an organization whose detection strategy depends on catching a ransomware executable would have seen nothing until the first endpoint rebooted and the ransom wallpaper appeared.

In this article, we will describe the GPO attack chain and provide operational advice on how to detect such threats, including detailed remediation recommendations.

Group Policy as an attack surface

Attacks through group policies are nothing new. They can inflict significant, domain-wide damage with multiple malicious capabilities. A Group Policy Object (GPO) is essentially a combination of a Group Policy Container (GPC) in Active Directory and a Group Policy Template (GPT) in SYSVOL. The Group Policy scope depends on whether the GPC is linked to the directory tree at the domain, site, or organization unit (OU) level. A link at the domain root means the policy applies to every computer and user object beneath it. Thus, a GPO compromised at the domain root can affect all in-scope domain users and computers, potentially granting an attacker complete control over the corporate network. What makes GPO abuse even more dangerous is that group policies are processed in a trusted, high-privilege environment, ensuring persistence because endpoint cleanup is not enough to remove them.

We have already discussed GPO architecture and ways it can be compromised in greater detail in an earlier blog post. Other public threat intelligence has also repeatedly documented this technique in ransomware operations. Microsoft observed Ryuk operators distributing ransomware through Group Policy, SYSVOL startup items, and PsExec. LockBit affiliates have been documented modifying SYSVOL Group Policy files, including ScheduledTasks.xml, to support ransomware execution and propagation. BlackCat/ALPHV operators have also abused GPOs to create scheduled tasks and deploy ransomware.

Another notable example of GPO abuse is PAYLOAD ransomware, which weaponizes GPO Preferences and policy settings for pure impact rather than as a launcher for an encryptor. Let’s take a closer look at this attack, which is detailed further below.

Attack timeline

During the April 2026 investigation, we managed to reconstruct the attack timeline as outlined below:

Date	Event
11 April	Initial access. Threat actor authenticates to the FortiGate SSL VPN using a valid but compromised domain credential.
13 April	GPO authored. Malicious GPO, PAYLOAD ({C897F2C7-C2AC-4E6F-BF48-58036FF29E79}) created and linked at the domain root, configuring ransom notes, wallpaper, lock screen, logon banner, and administrator account disablement.
13 April	SYSVOL staging. The payload.jpg and hello.txt files written to \\DC.THECOMPANY.local\sysvol\THECOMPANY.local\.
13 April	Second GPO. GPO named win Firewall Off ({22099AD2-E062-4F56-B574-5099BBA4E7A6}) linked at the domain root, disabling Windows Firewall on all profiles.
13 April	Dormancy. GPO cached on endpoints but computer configuration not yet applied — no endpoint had rebooted since the policy update.
13 April	Data exfiltration. Data exfiltration was observed originating from the file servers and several additional systems.
14 April	Detonation. Most of the endpoints begin rebooting; computer configuration policies apply. Ransom wallpaper, logon banner, and notes appear. Operational disruption begins.
15 April	Response. Kaspersky GERT engaged. Forensic triage of affected workstations and the domain controller initiated.
16 April	Assessment. GERT confirms no file encryption, no resident malware, no endpoint persistence.

Next, we will discuss each of these stages in more detail and share the findings from our incident response activities.

Incident overview

Initial access

The entry vector was a compromised valid account (MITRE ATT&CK T1078) used to authenticate through the organization’s FortiGate SSL VPN — an external remote service (T1133). Insufficient logging on the FortiGate appliance prevented us from reconstructing how the credential was originally compromised.

Three hypotheses were considered plausible in the context of the attack, in no particular order:

• Password spraying or credential stuffing against the SSL VPN portal.
• Phishing-led credential harvesting.
• Purchase of pre-compromised credentials from an initial access broker (IAB).

Once on the internal network, the actor operated with the compromised security principal’s privileges. Because the account was able to create and link a GPO at the domain root, it held either domain admin privileges or a delegated equivalent (e.g., membership of Group Policy Creator Owners combined with link rights on the domain object).

FortiGate SSL VPN authentication logs and ESXi/virtualization privilege escalation logs were insufficient to reconstruct the lateral movement and privilege escalation chain between initial VPN access and the GPO write privilege level. The most common real-world routes to GPO control — DCSync, Kerberoasting of privileged service accounts, and Pass-the-Hash/Pass-the-Ticket — could not be confirmed or ruled out.

Execution

Rather than deploying an encryptor, the actor abused the victim’s Active Directory policy infrastructure, resulting in malicious GPOs being configured and linked at the domain root to deliver the observed impact across domain-joined systems. The two GPOs below constitute the entire offensive toolkit observed.

The PAYLOAD GPO

We performed a Resultant Set of Policy (RSOP) analysis, which helped us list all policy settings on the affected workstations. From these results, we reconstructed the following changes delivered by PAYLOAD:

GPO extension/CSE	Setting/path	Configured value/resulting action
Files (Group Policy Preference)	Source SYSVOL\hello.txt → Desktop, C:\, D:\	Dropped as README-payload.txt (ReadOnly)
Registry (Computer)	HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\legalnoticecaption	Welcome to Payload!
Registry (Computer)	HKLM\…\Policies\System\legalnoticetext	(ransom demand text)
Personalization Policy	Lock Screen Image	\\DC.THECOMPANY.local\sysvol…\payload.jpg
Desktop Policy (User)	Wallpaper path	\\DC.THECOMPANY.local\sysvol…\payload.jpg
Security Settings (GptTmpl.inf)	Accounts: Administrator account status	Disabled

The PAYLOAD GPO enabled the following actions:

1. Drop SYSVOL\hello.txt to the desktop and root directories C:\ and D:\ as a read-only README-payload.txt by tampering with the “Group Policy Files” client-side extension (CSE).
2. Modify the HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\ registry key, changing the legalnoticecaption value to "Welcome to Payload!" and the legalnoticetext to the ransom note text through the “Group Policy Registry” CSE.
3. Set payload.jpg located in the targeted domain controller’s SYSVOL as the lock screen image by altering the personalization policy, and as the wallpaper by altering the desktop policy at the user level.
4. Revoke administrator rights for the administrator account (locking the account) by editing the Security Settings CSE in the GptTmpl.inf file.

Settings changed by PAYLOAD GPO

This activity was enabled entirely through a legitimate group policy mechanism, meaning there is no malware code for security solutions to look for because the malicious logic is contained within the policy configuration.

The win Firewall Off GPO

A second domain-root-linked GPO, named “win Firewall Off”, disabled Windows Firewall across the domain, private and public profiles on all endpoints (T1562.004). Deployed independently of PAYLOAD, this object degraded host defenses and ensured the actor retained unimpeded network reach to endpoints for any follow-on activity.

The one-day delay detonation

The most forensically instructive detail is the one-day gap between GPO creation (13 April) and visible impact (14 April). Analysis of Master File Table (MFT) timestamps and the Group Policy History registry key confirmed the policy was written to SYSVOL and cached on endpoints on 13 April. However, computer configuration settings (wallpaper and lock screen machine policy, security settings, firewall disabling) only apply upon reboot or policy refresh — and no endpoint had rebooted in the interim. The attack therefore remained dormant in the GPO cache for one day before detonating en masse when machines were restarted in accordance with standard procedures.

We have to point out here that this delayed policy application is characteristic of GPO-based operations and has two potential consequences for defenders. Firstly, it may grant the actor a quiet window for exfiltration, persistence, or further staging between weaponization and impact. Secondly, it can be used to sever the temporal link between the cause (a GPO-creation event in the directory log) and the effect (mass user-visible disruption occurring at a later time), complicating timeline reconstruction unless directory service auditing is in place.

Forensic findings

Initial incident response engagement revealed a number of findings associated with the attack that we share below.

1. No file encryption
   A full review of the MFT on affected workstations found no files bearing a .payload extension characteristic to PAYLOAD ransomware and no evidence of bulk renaming or encryption I/O patterns. The attackers’ objectives were operational disruption and extortion via visual impact and access denial.
2. No endpoint persistence
   All standard persistence locations were clean:
   • Scheduled tasks — no malicious tasks
   • Run/RunOnce keys — clean
   • Startup folders (user and system) — clean
   • Services — no malicious service installed
   • WMI event subscriptions — none
   • Boot sector/MBR — unmodified

   The attack’s persistence mechanism is the GPO link itself on the domain controller, with no endpoint-resident component.

3. No active malicious processes
   Live process and memory analysis revealed no injected threads, process hollowing or anomalous outbound connections.
4. Registry timeline analysis
   Group Policy History, Shadow and State registry keys on the workstation recorded the application of PAYLOAD on 13 April:
   HKLM\…\Group Policy\History\{35378EAC-683F-11D2-A89A-00C04FBBCFA2}\1
   HKLM\…\Group Policy\Shadow\{827D319E-6EAC-11D2-A4EA-00C04F79F83A}\0
   HKLM\…\Group Policy\State\Machine\GPO-List\7
   HKCU\…\Group Policy\History\{7150F9BF-48AD-4da4-A49C-29EF4A8369BA}\1
   HKCU\…\Group Policy\State\S-1-5-21-…\Loopback-GPO-List\5
   The presence of the “Loopback-GPO-List” entry indicates the GPO was processed in loopback mode, ensuring the user configuration (wallpaper) applied regardless of which user logged on to the machine.
5. SYSVOL artifacts
   Two files were staged on the domain controller’s SYSVOL share and served to endpoints through the Files Group Policy Preference CSE:
   • payload.jpg — the ransom image used for both wallpaper and lock screen.
   • hello.txt — the ransom note, distributed to desktops and drive roots as README-payload.txt.

Detection engineering

Because no malicious binary or process exists, the detection logic should focus on the directory service and SYSVOL indicators. Below are the highest-value telemetry sources for identifying the described malicious activity.

• Directory service change auditing (DS Access)
  Enable Advanced Audit Policy → DS Access → Audit Directory Service Changes on all domain controllers and set up alerts for the following events:

  Event ID	Meaning	Hunt focus
  5137	A directory service object was created	The account that created new groupPolicyContainer objects must be an authorized GPO administrator
  5136	A directory service object was modified	Changes to gPLink on the domain root or sensitive organizational units; changes to gPCMachineExtensionNames/gPCUserExtensionNames/gPCFileSysPath/versionNumber for all GPOs
  5141	A directory service object was deleted	GPO deletions (relevant for tamper detection and remediation assessment)

  A gPLink modification at the domain root by a non-standard account is one of the most telling indicators of this attack class.

• SYSVOL file integrity monitoring
  Monitor \\DC.THECOMPANY.local\sysvol\THECOMPANY.local\Policies\ for unexpected files, particularly image files, text files, scripts, ScheduledTasks.xml, and modified registry.pol/GptTmpl.inf files that were created by sources other than legitimate replication.
• Endpoint policy application telemetry
  On endpoints, GPO application is logged in the Group Policy Operational log (Microsoft-Windows-GroupPolicy/Operational) and reflected in the History and Shadow registry keys shown above. A sudden domain-wide change to the applied policy set is a strong post-detonation signal.
• Missing 5136 events
  If the contents of a GPO’s SYSVOL change without a corresponding 5136 event, this can indicate direct SYSVOL/template editing (e.g., via open-source tools such as PowerView or SharpGPOAbuse) that bypasses the normal Group Policy Management Console (GPMC) modification path. While we recommend treating the absence of expected audit events as suspicious, it should be noted that this can be caused by misconfigured auditing.

Anti-forensics and recovery-inhibition capabilities

Confirmed PAYLOAD family capabilities

The Windows endpoint attack described in this report was implemented through malicious Group Policy Objects and did not involve a recovered ransomware executable, resident endpoint malware, confirmed file encryption or active malicious processes at the time of the forensic examination. However, PAYLOAD cryptomalware for Windows does exist, and other sources, including public analysis of its samples, reveal further malicious capabilities of this ransomware that could be used by security teams to enrich detection logic and security policies.

The behaviors documented in this section must therefore be interpreted as family-level capabilities identified through the public reverse engineering of PAYLOAD ransomware samples. They were not confirmed as having executed during the GPO-based incident unless corresponding evidence was identified in the host, memory, process, event-log, or hypervisor.

Windows Event Log clearing

Public reverse engineering of the PAYLOAD Windows variant reveals an optional event log clearing capability (T1685.005, formerly T1070.001). The ransomware dynamically resolves Windows Event Log APIs, enumerates available event log channels, and clears individual channels.

Implementation artifacts include:

• Runtime loading of wevtapi.dll
• EvtOpenChannelEnum
• EvtNextChannelPath
• EvtClearLog
• Enumeration of Security, System, Application, and PowerShell logs, and operational channels
• A command-line option controlling whether log clearing is performed

Clearing event logs reduces the availability of records related to process execution, authentication, PowerShell, service control, and system changes. However, it does not necessarily remove events that were already forwarded to a SIEM, Windows Event Collector, EDR backend, or protected log archive.

Forensic indicators

• Windows Security Event ID 1102
• Event logging shutdown or failure events
• Sudden reductions in event record identifiers
• Multiple event channels restarting from low record numbers
• Gaps between endpoint and centrally forwarded telemetry
• Execution of utilities or APIs associated with log management
• Direct access to EVTX files (Windows Event Log files) under the Windows event log directory

We should note that these indicators can’t be interpreted on their own. For instance, Event ID 1102 should be correlated with a number of aggravating factors, such as:

• Event ID 4688 or Sysmon Event ID 1 for process creation
• Event ID 4624 for the associated administrative logon
• EDR process trees
• PowerShell operational logging
• Windows Event Forwarding records
• Privileged access management activity

At the same time, the absence of Event ID 1102 does not prove that log clearing did not occur. Direct deletion, truncation, service impairment, or an incomplete audit configuration may produce different evidence.

Security process and service termination

PAYLOAD analysis reveals that the Windows ransomware variant contains logic that targets security processes and services (T1685 and T1489). This capability is intended to stop security products, backup software, database services, and applications that may lock files targeted for encryption.
Process and service termination serves several objectives:

1. Reduce endpoint detection and response visibility.
2. Release file handles so data can be modified.
3. Interrupt backup and recovery services.
4. Prevent databases and enterprise applications from protecting active data.
5. Reduce interference with encryption operations.

Forensic indicators

• Security agent services changing from running to stopped
• Event ID 7036 service state changes
• Event ID 7040 service start type changes
• Event ID 4688 or Sysmon Event ID 1 for service control utilities
• Sysmon Event ID 5 for terminated processes
• EDR health degradation affecting many endpoints
• Repeated termination attempts against security or backup processes
• Execution of dedicated process killing utilities

VSS deletion, backup and recovery suppression

Public PAYLOAD sample analysis reports the deletion of Windows Volume Shadow Copies before encryption (T1490). This behavior removes local restore points and reduces the victim’s ability to recover files without external backups.

Recovery inhibition is broader than VSS deletion and may include multiple other malicious techniques, including the following:

• Deleting shadow copies, backup catalogs, and hypervisor snapshots
• Disabling recovery services
• Modifying boot recovery settings
• Compromising backup management platforms
• Deleting or encrypting backup repositories

In the PAYLOAD Windows sample that is proven to perform encryption, VSS deletion is confirmed to have taken place before encryption. A broader compromise of the backup platform was not established in the investigated incident.

Forensic indicators

• Execution of shadow copy management utilities
• Backup catalog deletion attempts
• Recovery configuration changes
• Backup service termination
• Mass snapshot deletions
• Backup administrator logons outside normal maintenance windows
• Backup retention or immutability changes
• Backup jobs failing immediately before disruptive activity

Ecosystem-relevant ransomware techniques

Above, we discussed the techniques specific to PAYLOAD ransomware. In this section, we’ll review other common ransomware techniques, such as BYOVD abuse and ESXi policy weakening, that remain relevant risks in the ransomware ecosystem. However, these techniques should not be attributed to this incident without supporting driver load, process, memory, ESXi, vCenter, or backup platform telemetry. We describe these techniques below as they may prove useful in other ransomware-related forensic investigations.

The examples used in this section are therefore ecosystem-relevant: they are commonly observed in ransomware operations but not conclusively attributed to the analyzed PAYLOAD samples.

ETW suppression and in-memory patching

Event Tracing for Windows (ETW) is a kernel-supported tracing architecture used by Windows components, diagnostic utilities, security products, and endpoint monitoring systems.

Although we didn’t encounter this technique in our case, some ransomware families can patch ETW-related functions inside the ransomware process (T1685, formerly T1562.001). The reported routine changes the memory protection of code pages, overwrites the beginning of selected ETW functions so they return without producing events, restores the original protection, and refreshes the instruction cache.

Reported target functions include EtwEventWrite, EtwEventWriteFull, EtwEventWriteTransfer, and EtwRegister.

This modification applies to the process-local mapping of ntdll.dll. It does not disable ETW globally across Windows, but it can reduce the telemetry generated by the modified process.

Forensic indicators

• Writable or recently modified executable pages within ntdll.dll
• Memory protection changes affecting ETW function addresses
• In-memory code differing from the corresponding clean DLL on disk
• EDR memory tampering alerts
• Unexpected calls to memory protection APIs followed by telemetry silence
• Process execution visible in network or filesystem telemetry but absent from expected ETW-derived sources
• Inconsistent telemetry between EDR, Sysmon, Windows Event Logs, and network monitoring

It should be noted that telemetry gaps are not conclusive evidence of ETW patching. Other factors include agent upgrades, network outages, endpoint shutdowns, SIEM ingestion failures, collector backpressure, and filtering or licensing changes.

Memory acquisition is the strongest validation source when process-local ETW patching is suspected.

Vulnerable signed driver abuse, BYOVD

Bring Your Own Vulnerable Driver (BYOVD) involves introducing or abusing a legitimately signed but vulnerable kernel driver (T1068 and T1685). The attacker exploits the driver’s exposed functionality to gain kernel-level capabilities, modify protected memory, terminate security processes, remove security callbacks, or bypass operating system security controls.

BYOVD is highly relevant to contemporary ransomware operations. However, the reviewed public PAYLOAD analyses do not provide sufficient evidence to conclude that BYOVD is an intrinsic PAYLOAD capability.

It should therefore be presented as an ecosystem-relevant technique rather than a confirmed PAYLOAD feature.

Forensic indicators

• Unexpected .sys files written to user-writable or temporary directories
• New kernel driver services
• Sysmon Event ID 6
• Driver hashes matching Microsoft or community vulnerable driver blocklists
• Invalid, revoked, expired, or unusual driver signatures
• Driver load followed by EDR termination
• New privileged processes immediately following driver loading
• Code Integrity or Defender alerts
• Service creation events referencing driver files

ESXi security policy weakening

Ransomware operators are increasingly targeting ESXi and vCenter because compromising the virtualization layer provides access to many business-critical virtual machines.

Public research typically describes operators performing the following activities (T1685, T1490 and T1489):

• Enabling SSH on ESXi hosts
• Changing root passwords
• Disabling execInstalledOnly
• Modifying lockdown mode exceptions
• Stopping virtual machines
• Deleting snapshots and backups
• Changing host firewall policies
• Copying custom ransomware binaries to hypervisors

On the target organization’s Linux servers we saw an ESXi PAYLOAD variant, which makes this behavior operationally relevant. Nevertheless, the reviewed evidence does not indicate that PAYLOAD operators used any of these policy-weakening actions in the investigated incident.

Forensic indicators

• Unexpected ESXi SSH enablement
• Changes to execInstalledOnly
• Secure Boot enforcement changes
• Lockdown mode configuration changes
• Root password changes
• New or unusual administrator accounts
• Bulk VM shutdown activity
• Bulk snapshot deletion
• New binaries in datastore or temporary paths
• vCenter tasks originating from unexpected accounts or systems
• Missing or disabled remote syslog forwarding

Remediation

To contain the described threat and limit possible damage, several remediation steps should be taken. Below, we recommend a four-phase remediation approach for containing this threat and restoring the affected environment.

Phase 1 — domain controller actions (to be performed first)

When dealing with PAYLOAD GPO, the first priority of the remediation plan should be to remove the source GPOs. Until this is done, endpoint cleanup is ineffective because the next policy refresh re-infects cleaned machines.

The immediate domain controller actions to be taken are:

1. Delete PAYLOAD GPO. Remove {C897F2C7-C2AC-4E6F-BF48-58036FF29E79} via GPMC.
2. Delete or revert win Firewall Off GPO. Remove {22099AD2-E062-4F56-B574-5099BBA4E7A6}.
3. Clean SYSVOL. Delete jpg and hello.txt from \\DC.THECOMPANY.local\sysvol\THECOMPANY.local\.
4. Rotate credentials. Reset the compromised account; audit all privileged accounts and group memberships for unauthorized changes; rotate krbtgt twice if domain admin compromise is confirmed.
5. Force refresh. Perform gpupdate /force across endpoints after deletion; re-enable local administrator and firewall via clean policy.

Phase 2 — Active Directory and GPO hardening

• Adopt the AD tiered administration model and confine domain admins to Tier 0 with no interactive logon to workstations and member servers.
• Separate GPO creation from GPO linking rights, and grant both only to a dedicated, audited administrator role.
• Enable GPO change auditing (Event IDs 5136, 5137, 5141) and forward to a SIEM.
• Monitor SYSVOL with file integrity tooling.

Phase 3 — credential and access hardening

• Enforce phishing-resistant MFA on all VPN and remote access entry points.
• Deploy Windows LAPS to generate unique, rotated local administrator passwords.
• Enable Credential Guard to protect LSASS-resident secrets.
• Adopt Privileged Access Workstations (PAW) for all administration.
• Implement just-in-time elevation through Privileged Identity Management (PIM) for domain admin.

Phase 4 — detection and monitoring

• SIEM rule: GPO creation or domain-root gPLink change by a non-standard account.
• SIEM rule: file creation events under SYSVOL from non-replication sources.
• Implement enhanced, centrally collected FortiGate SSL VPN logging (auth events, session detail, source IP geolocation, impossible travel check) and detailed perimeter monitoring.
• Deploy a canary GPO whose application anywhere signals attacker GPO write access.

Conclusion

PAYLOAD demonstrates a maturing tactic of turning the victim’s own trusted infrastructure into a weapon. By weaponizing Group Policy, the actor achieved a domain-wide impact without a single malicious binary on any endpoint, evaded file- and process-based detection entirely, and caused organization-wide disruption within seconds of the first reboot.

The absence of encryption is the most strategically significant finding and is consistent with the 2026 trend toward encryptionless extortion. At Kaspersky GERT, we assess with moderate confidence that the missing encryption reflects one of two scenarios: (1) a deliberate decision to stay below the irreversible data destruction threshold while preserving the option of a follow-on encryption phase, or (2) an operation interrupted before full execution.

The absence of encrypted files must not be mistaken for the absence of a serious compromise — the most critical impact lies in the actor gaining domain admin-level control. This incident proves that a threat actor with domain admin access and a working knowledge of group policy internals can inflict domain-wide disruption equivalent to a ransomware attack without writing a single malicious file to any endpoint.

Detection strategies anchored solely in file- or process-based indicators are blind to this attack class. Effective controls include directory service change auditing, SYSVOL integrity monitoring, and privileged access governance, which allow for GPO protection.

Detection by Kaspersky solutions

Kaspersky security solutions effectively detect the described malicious activity at various stages of the attack. Possible detection scenarios are listed below.
To protect organizations that use our Kaspersky SIEM system, we have prepared a package of correlation rules designed to help detect this type of malicious activity. The rules are now available for customers to download from the SIEM repository; the package name is: [OOTB] Group policy hijacked: PAYLOAD ransomware – ENG.

The “Group policy hijacked: PAYLOAD ransomware” package contains rules that detect suspicious file creation or modification in the SYSVOL shared folder on a domain controller, as well as changes to critical attributes and settings of domain group policies. Some rules may require adjustment if they trigger in response to legitimate activity, such as synchronization between domain controllers or the configuration of a new group policy.

To ensure the detection rules function correctly, verify that events from Windows systems are being received in full, including events with the following identifiers: Sysmon: 11, Security — 4663, 5136, 4657.

We also recommend applying the following rules available in the repository to detect all attack stages.

• Detection of Windows Event Log clearing to cover up traces of an attack: R050_03_Windows Event Log was cleared
• Detection of suspicious access to the LSASS process, which may indicate attempts to dump credentials: R262_Suspicious access to the LSASS process
• Detection of the Volume Shadow Copy service being started, which is used to create shadow copies before deleting them: R231_20_Running the Volume Shadow Copy service
• Detection of shadow copy deletion: R321_Shadow copy deletion
• Detection of Windows Defender disablement: R076_01_Windows Defender Antivirus was disabled
• Detection of attempts to disable or modify the system firewall: R240_03_Disabling system firewall via the registry
• Detection of a service installation from a non-system folder, which may indicate malware persistence techniques: R281_01_Installation of a service from a non-system folder

For the rules in this list to function correctly, it is necessary to configure Security event auditing for event IDs 4663, 5136, 4657, 7036, and 1102.

In addition to the SIEM system, when audit settings are configured correctly, the process of creating, modifying, and deleting GPOs generates a large number of characteristic artifacts on the domain controller, enabling Kaspersky Endpoint Detection and Response Expert to promptly alert the user to anomalies in the infrastructure.

The creation of a new GPO is covered by the gpo_creation rule, which triggers in response to the corresponding event in the infrastructure. Changes to existing policies are detected by the following rules:

• The setting_the_gpcmachineextensionname_attribute rule detects changes to the gPCMachineExtensionNames attribute.
• The setting_the_gpcfilesyspath_attribute rule detects the use of the gPCFileSysPath attribute of a Group Policy Object, which specifies the path to the GPO’s contents in SYSVOL.
• The broader rule setting_the_grouppolicycontainer_class detects a change to the groupPolicyContainer class.

GPO deletion is covered by the gpo_deletion rule.

In the next major version update of Kaspersky EDR Expert, a new event type, GPO, will be introduced, allowing users to track changes to Group Policy Objects.

For information security officers, GPO events will serve as an additional source of context when investigating activity in Active Directory and will help detect changes that could affect the configuration, access rights, and security of endpoints before a potentially malicious policy is deployed.

MITRE ATT&CK mapping

Tactic	Technique	Observed behavior
Initial Access	T1078 — Valid Accounts	Compromised domain credential used for VPN authentication
Initial Access	T1133 — External Remote Services	FortiGate SSL VPN used as entry point
Privilege Escalation	T1078.002 — Domain Accounts	Account held domain-level GPO create/link rights
Privilege Escalation/Defense Impairment	T1484.001 — Group Policy Modification	Malicious PAYLOAD GPO created and linked at domain root; re-applies on every refresh/reboot; uses trusted channel to evade EDR
Defense Impairment	T1686 — Disable or Modify System Firewall	win Firewall Off GPO disables Windows Firewall on all profiles
Impact	T1491.001 — Internal Defacement	Wallpaper and lock screen replaced with ransom image
Impact	T1531 — Account Access Removal	Local Administrator account disabled via GPO Security Settings
Collection	T1005 — Data from Local System	Data exfiltration was observed originating from the file servers
Command and Control	T1071 — Application Layer Protocol	No live C2 confirmed; delivery achieved entirely via GPO

Indicators of compromise

GPOs
PAYLOAD ransomware GPO: {C897F2C7-C2AC-4E6F-BF48-58036FF29E79}
win Firewall Off GPO: {22099AD2-E062-4F56-B574-5099BBA4E7A6}

File names and MD5 hashes
payload.jpg: Ransom wallpaper and lock screen image (SYSVOL)
hello.txt: Ransom note source (SYSVOL)
README-payload.txt: Ransom note dropped to desktops and drive roots
killer.exe (0108656A3E1ADE6CA4F21B084F5E1208): process killer tool
kill.exe (BEA5E267F24D7DA59F6821BFFDBFF293): process killer tool

IP addresses
37.19.210[.]12
146.70.117[.]239
149.102.229[.]154
104.164.55[.]46
104.28.162[.]228
104.28.163[.]162
64.190.76[.]14
192.42.116[.]50
192.42.116[.]12
192.42.116[.]56
192.42.116[.]97
192.42.116[.]52

Registry keys
HKLM\...\Policies\System\legalnoticecaption = Welcome to Payload!

SYSVOL path
\\DC.THECOMPANY.local\sysvol\THECOMPANY.local\payload.jpg

Event IDs
5137: GPO object creation on DC — review creator account
5136: GPO attribute modification — watch gPLink at domain root

This is interesting:

The records describe a force-generation mechanism for several General Staff components, including the GRU, Main Operational Directorate, and 8th Directorate, which is associated with protected communications, cryptography, and information security.

[…]

The reporting also linked a 2024 Department No. 4 graduate, Aleksei Kondrashov, to Military Unit 74455, widely known as Sandworm.

That unit has been associated with destructive cyber activity against Ukraine and other targets, including the 2017 NotPetya attack.

The reports do not establish that every listed graduate participated in a named operation; assignments should therefore be described as reported unit placements, not proof of individual operational involvement.

The Bauman material reframes Russia’s cyber capability as an institutional system, not merely a collection of well-known threat groups.

It suggests that Moscow has formalized a recurring pathway from university recruitment to military service, where students receive supervised technical and ideological preparation before entering intelligence, cyber, and security roles.

For defenders, the leak reinforces the need to track Russian operations as a combined threat: espionage, destructive activity, military reconnaissance, technical surveillance, and influence campaigns may draw on related personnel pipelines and overlapping doctrine.

The exposure of Department No. 4 also provides researchers with a clearer lens for understanding how the GRU sustains cyber capacity beyond the familiar APT28 and Sandworm brand names.

Brazil's SISVISA health surveillance system left 102,215 files totaling 79GB open online, including tax IDs and identity documents, without password protection.

Purpose and Scope This report summarizes the quantity of ransomware samples collected, the number of affected systems, statistics on targeted businesses, and major Korean & global issues during the month of June 2026. Statistics on targeted businesses were compiled based on information posted on DLS (Dedicated Leak Sites) operated by ransomware groups, which publish details […]

Leaked Tata files reportedly show possible iPhone 18 Pro design details, factory images, and supplier records ahead of Apple’s expected September launch.

The post iPhone 18 Leak: Apple’s Next Pro Design May Have Appeared Online appeared first on TechRepublic.

Small and medium-sized businesses (SMBs) remain attractive targets for cybercriminals – in both mass cyberattacks and sophisticated campaigns targeting larger enterprises through trusted relationship attacks. At the same time, smaller businesses may lack the robust cybersecurity policies and necessary resources to protect themselves against an evolving threat landscape.

Kaspersky believes that raising awareness can help small and medium-sized enterprises develop an effective protection strategy. Ahead of International SMB Day on June 27, Kaspersky presents the findings of its 2026 threat analysis for SMBs, which includes real-world examples of attacks.

Key findings

• In the first four months of 2026, Kaspersky solutions detected over 33,300 cyberattacks on SMBs masquerading as popular artificial intelligence (AI) tools – almost five times more than in 2025 and 39% more than the number of attacks disguised as the office and collaboration tools that Kaspersky’s research focuses on.
• Popular messengers and communication services remained the attacker’s most widespread lure, with almost 415,000 attacks involving fake messenger apps and video conferencing software.
• The attackers follow trends: the AI tools Claude and OpenClaw (ex-ClawdBot/MoltBot), which have gained popularity in 2026, were among the common AI lures.
• Fraudsters use fake AI tools to scam businesses out of money, while corporate accounts on social media also remain targets.
• The majority of initial accesses to corporate infrastructures sold on the dark web are allegedly accesses to SMBs. This could be because SMBs tend not to be as well protected as large enterprises and, at the same time, may be trusted contractors for those well-protected enterprises.

Malware and potentially unwanted applications (PUAs) disguised as popular services

Kaspersky researchers used data from Kaspersky Security Network (KSN) to explore how frequently malicious and unwanted files are disguised as legitimate applications that may be used by SMBs. KSN is a system for processing anonymized cyberthreat-related data shared voluntarily by Kaspersky users. For this part of the report, only anonymized data received from users of Kaspersky solutions for SMBs were analyzed.

According to a survey by the Small Business & Entrepreneurship Council (SBE Council), small business owners continue to embrace artificial intelligence and digital transformation as they maintain a generally positive outlook on the economy. Threat actors are also aware of the hype surrounding AI and exploit it for their own benefit. In particular, they actively distribute cyberthreats under the guise of popular AI services.

From January to April 2026, Kaspersky solutions detected 33,352 attacks on SMB users in which malware or potentially unwanted applications for PCs were disguised as five popular AI services. This figure represents an increase of almost five times compared to the previous year. This highlights an evolving trend in which threat actors are weaponizing trust in widely used AI platforms and services, especially popular ones like Claude. Kaspersky experts note that it’s important to download apps from official sources and to verify which apps are available for which platforms.

Share of attacks targeting SMBs in which malware or PUAs mimic the five popular, legitimate AI apps that Kaspersky’s research focuses on, first four months of 2025 and 2026 (download)

In the first four months of 2026, Kaspersky researchers also identified more than 1,100 unique samples of malware and PUAs detected in the SMB sector that masqueraded as five popular AI applications, representing a 21% increase compared to the same period of 2025. The samples were mainly different types of Trojware (Trojans and Trojan-like malware), including those capable of downloading and running other malware on compromised devices. Trojware disguises itself as harmless files to trick users into installing them. Their functionality may vary depending on the particular type of Trojware. This may include stealing, deleting, blocking, modifying or copying users’ data, as well as other malicious actions. Trojware therefore represents a highly dangerous cyberthreat to entrepreneurs and businesses.

Kaspersky experts also note that the threat landscape is constantly evolving with new lures appearing all the time. For example, in the first four months of 2026, Kaspersky solutions blocked hundreds of attacks in which malware or PUAs for PCs were disguised as OpenClaw (previously known as Clawdbot or Moltbot).

Other lures for SMBs: Fake communication apps and office software

Kaspersky analysts also explored how attackers leverage other legitimate applications as lures to target SMBs. For example, from January to April 2026, Kaspersky solutions blocked 414,736 attacks on SMB users in which malicious software or PUAs for PCs were disguised as the popular communication apps that Kaspersky’s report focuses on. The number of attacks changed marginally compared to the previous year’s figure, indicating that the lure of fake communication apps remains a serious cyberthreat.

Share of attacks targeting SMBs in which malware or PUAs mimic the four legitimate communication apps covered by Kaspersky’s research, first four months of 2025 and 2026 (download)

Various fake office applications and collaborative platforms also remain among the lures that attackers may exploit to target SMBs. According to Kaspersky telemetry, more than 24,000 attacks were detected from January to April 2026 in which malware or PUAs for PCs were disguised as specific office applications.

Share of attacks targeting SMBs in which malware or PUAs mimic the six popular office applications and collaboration tools covered by Kaspersky’s research, first four months of 2025 and 2026 (download)

In 2026, AI-related baits have become more widespread among cybercriminals than traditional fake office and collaboration tools. Kaspersky experts note that the more publicity and hype there is around certain tools, the more likely a user is to come across a fake package online.

Scammers and phishers tricking victims into providing credentials and funds

In 2026, Kaspersky researchers observed a wide range of phishing campaigns and scams targeting businesses and entrepreneurs. Fraudsters mimic financial and AI services as well as other platforms in order to steal credentials, personal information and funds.

In the following example, fraudsters disguise themselves as a bank that allegedly offers services for businesses (in other similar schemes they may offer business loans). Entrepreneurs are prompted to visit a scam website and enter their data to open a business account. The requested information varies depending on the scam, but may include name, email address, phone number, social security number, date of birth and address. Scammers may then use this data in their schemes or sell it on the dark web.

Kaspersky experts advise: if you encounter such a website, you should not rush to enter any data. First, examine it. Does the purported financial organization actually exist? How old is the website? Check the WHOIS records and read user reviews before entering any information on the page.

As with many other cyberthreats, AI services are also leveraged as a lure in scams. For example, Kaspersky experts identified a scam website for an AI service “built for contractors”. According to the text on the fraudulent page, the tool can help with “estimates, invoices and schedule”. However, in reality, in such schemes victims usually receive nothing after paying for a subscription, while the scammers get all the money.

Kaspersky experts note that business accounts on social networks and messengers remain attractive targets for cybercriminals in 2026. In one scheme, phishers distributed notifications with fake alerts related to companies’ business pages. The notifications claimed that Facebook’s review system had detected behavior that seriously violated its Community Standards and Advertising Policies. To avoid permanent restriction of their business page on the social network, owners were prompted to fill out an appeal form and provide personal and business email addresses, phone numbers, as well as the name of their business page and the password for their social network account. The attackers’ goal was to obtain credentials. To reduce user vigilance  and appear legitimate, fraudsters also sent victims a fake appeal code.

Email threats: Fake online documents and exploitation of legitimate platforms

Email remains one of the most widely used channels for cyberattacks targeting enterprises, including small and medium-sized businesses. In 2026, attackers have frequently combined email distribution with the exploitation of legitimate third-party platforms. This is how phishers and scammers usually attempt to bypass traditional email filters and exploit user trust in reputable services. Kaspersky researchers have also observed a large number of schemes targeting corporate users in which phishers and scammers use fake online documents or nonexistent meetings as bait.

In one recent scheme detected by Kaspersky, the attackers sent a fake notification disguised as a letter from OneDrive. The victim was prompted to access the document by clicking a button, but in reality, it led to a phishing website where users risked losing their confidential data. To make the email appear legitimate, the attackers added a phrase designed to  lower the victim’s vigilance: “This item is encrypted and hosted within your secure cloud perimeter.” They also parsed the recipient’s email address and used the extracted data in the fake notification text so that the email looked like a standard notification from this type of service: “[email address domain as company name] has successfully uploaded a new file for [the user’s name as stated in their email address].”

Attackers also use other pretexts to trick victims into sharing confidential information, for example fake compliance issues. In the example below, the attackers posed as Apple representatives. The fake notification stated: “Apple has identified a compliance issue related to Google Ads campaigns directing traffic to Apple product detail pages associated with the victim’s seller account.” However, the button in the email led to a phishing website where users are tricked into sharing confidential data.

Kaspersky experts observed another notable two-stage scheme aimed at stealing credentials from corporate emails, which involved distributing an invitation to a nonexistent meeting. The scheme is deployed in two stages. In stage one, a corporate user receives an email about a fictitious meeting. After clicking the “Accept Meeting Invitation” button, the user is redirected to a legitimate Zoom Docs (previous Zoom canvas brand) page. In stage two, the victim is prompted to click a hyperlink that reads “Click Here to Accept Meeting”. However, the URL of a phishing page is hidden behind this hyperlink.

Malware is also actively distributed via email. In 2025, individuals and corporate users encountered over 144 million malicious and potentially unwanted email attachments, representing a 15% increase from the previous year.

Kaspersky experts note that the lures used in subject lines and texts of malicious emails can appear relatively harmless and rather unsophisticated. In the example below, the attackers target businesses with a fake request for “the best quote for the items attached.” However, the attached file actually contains a Trojan.

Corporate infrastructure access for sale: Posts on the dark web

To assess threat actor activity, Kaspersky Digital Footprint Intelligence experts analyzed hundreds of posts offering initial access to corporate infrastructures published on dark web forums from January to April of both 2025 and 2026. Kaspersky experts note that a single post may contain several offers for access to different allegedly compromised companies.

Initial access brokers (IABs) sell initial access to compromised businesses, for example, via RDP or web shells. In their posts, IABs may provide information about the region where the allegedly compromised companies are located, their industry and revenue, as well as the type of access. IABs sell access that the buyers can then use for different purposes, including ransomware attacks, stealing corporate confidential information or other fraudulent activity. The price of initial access on dark web forums may depend on the revenue, industry or location of the allegedly compromised companies, or on the access privileges. For example, accounts with admin rights are usually more expensive because they can provide attackers with a wide range of possibilities.

According to the research, there were more posts offering initial access to companies of different sizes located in the Middle East (up 53% from last year), Africa (up 40%) and Latin America (up 17%). Meanwhile the number of posts related to companies located in Europe decreased by 34%. According to Kaspersky experts, this decline can be partially explained by the closure of a dark web forum containing such posts around the time of the study. The number of publications related to companies located in the APAC region also decreased slightly (down 4%), but remained at a consistently significant level for the second year in a row.
At the same time, the number of posts where the region was not specified decreased by 56% in 2026 compared to the previous year. Kaspersky analysts assume that this may indicate that initial access posts from IABs are becoming more targeted and unique.

Share of posts with initial access offers by business size

For this research, Kaspersky experts defined a small business as having an annual revenue of up to US$50 million, and a medium-sized business as having an annual revenue of between US$50 million and US$1 billion.

According to Kaspersky’s research, at the beginning of 2026 the share of posts on dark web forums with offers of initial access to allegedly compromised small businesses was larger than the shares of posts offering access to medium, large or nonprofit organizations. However, this share decreased in the first four months of 2026 compared to the same period in 2025. The share of posts concerning medium‑sized organizations also remained significant for two consecutive years. Taken together, posts concerning small and medium‑sized organizations account for more than half of all the analyzed posts with initial access offers on dark web forums.

At the same time for a certain number of posts initial access brokers didn’t indicate companies’ revenue, therefore, making it impossible to determine the size of the company.

Share of posts with initial access offers by business size, January–April 2025 (download)

Share of posts with initial access offers by business size, January–April 2026 (download)

Kaspersky experts note that despite the prevalence of posts concerning small businesses, threat actors may target medium‑sized businesses because they generate higher revenues than small businesses and may have weaker security defenses than large businesses.

SMBs can also become targets as a part of trusted relationship attacks, which enable the attackers to reach larger organizations. According to the Global Report by Kaspersky Security Services, the share of trusted relationship attacks among the initial vectors increased from 12.7% in 2024 to 15.5% in 2025. Therefore, the common belief that small and medium‑sized enterprises are of no interest to attackers is a misconception. Companies of all sizes need to understand the cyberthreat landscape, adhere to cybersecurity rules, implement appropriate cybersecurity solutions, and continuously improve employee awareness.

Cybersecurity action plan for SMBs

SMBs can reduce risks and ensure business continuity by investing in comprehensive cybersecurity solutions and increasing employee awareness. To protect themselves from the ever-evolving threat landscape, companies are advised to follow these rules:

1. Define access rules for corporate resources such as internet services, email accounts, shared folders, and online documents. Keep access lists up to date and revoke access promptly when employees leave the company.
2. Regularly back up important data to ensure the preservation of corporate information in case of emergencies.
3. Establish clear guidelines for using external services and resources. Create well-defined procedures for coordinating specific tasks, such as implementing new software, with the IT department and other responsible managers. Develop short, easy-to-understand cybersecurity guidelines for employees, with a special focus on account and password management, email protection, and safe web browsing. A well-rounded training program will equip employees with the necessary knowledge and ability to apply it in practice.
4. Raise employees’ security awareness. Conduct dedicated training to teach staff how to detect and address potential threats, and track their educational progress. Organizations can achieve this with the Kaspersky Automated Security Awareness Platform through interactive online modules and simulated phishing campaigns that build sustainable cyber hygiene habits across all teams.
5. Implement specialized cybersecurity solutions that fit your budget, size, and industry requirements, with an emphasis on scalability and ease of integration.
   1. Kaspersky Small Office Security Premium is an easy-to-use solution that protects against advanced threats and also provides access to security awareness training for employees, making it ideal for micro-businesses.
   2. Small and medium-sized enterprises with more mature IT expertise should consider Kaspersky Next Optimum, which is designed specifically for growing organizations and offers real-time protection, threat visibility, as well as EDR and XDR investigation and response capabilities.
6. Protect your business against email-borne threats. Kaspersky Security for Mail Server, a comprehensive email security platform that offers robust, multi-layered protection at mailbox and gateway levels, can help with this. Powered by machine learning and leading global threat intelligence, it effectively addresses all mail security challenges.
7. Adopt specialized solutions such as Kaspersky Digital Footprint Intelligence to monitor the surface, deep, and dark webs for information about a company’s credentials, leaked data, and lookalike websites. Small and medium-sized companies with limited IT security budgets can partner with a managed security service provider (MSSP) to access this comprehensive digital risk protection service at an affordable, subscription-based price point.

Tata Electronics is investigating a cyber incident after leaked files reportedly included manufacturing documents for Apple and Tesla.

The post Tata Electronics Leak Exposes 200,000 Files, Including Apple and Tesla Documents appeared first on TechRepublic.

Introduction

Mexico is one of the host countries for the 2026 FIFA World Cup, with matches to be played in three major cities: Mexico City, Monterrey, and Guadalajara. These locations are expected to see a large influx of international visitors, increasing the potential security risks. Many of those risks arise from users connecting to public wireless networks.

To better understand the wireless environments that visitors may encounter, we at Kaspersky GReAT conducted a wardriving assessment in the three host cities. The aim of the study was to analyze characteristics, deployment patterns, security configurations and potential exposure risks of public Wi-Fi infrastructure in urban wireless environments.

The information collected during the assessment was used exclusively for passive observation and infrastructure analysis. No attempts were made to authenticate, intercept communications, exploit systems or interact with the detected wireless networks beyond the publicly broadcast management information.

During processing of the collected data, one step involved filtering out networks belonging to cars or cell phones categorized as mobile hotspots because they do not represent networks that can be considered part of the assessment.

Research scope

The cities included in the study have high population density and extensive wireless infrastructure deployments. We chose areas with the most prominent wireless network activity and highly concentrated public access points. We carried out wardriving research in Monterrey back in 2008, but the city’s hotspot landscape has changed since then.

We chose the following analysis areas for each of the cities:

1. Mexico City: México City Stadium, Mexico City International Airport, Zócalo, Paseo de la Reforma, Colonia Roma, La Condesa, Polanco, and Coyoacán.
2. Guadalajara: Guadalajara Stadium, Guadalajara International Airport, the city center, Zapopan, Providencia, Avenida Chapultepec, Colonia Americana, Tlaquepaque, and the area around Andares.
3. Monterrey: Monterrey Stadium, Monterrey International Airport, Fundidora Park, Cintermex Monterrey, the downtown area, Barrio Antiguo, MacroPlaza, and the San Pedro financial district.

The wireless information was collected using passive wireless reconnaissance techniques. The collected information included:

• SSID analysis and information exposure, including BSSID-derived SSIDs
• Default router configurations and ISP deployments
• Frequency and signal characteristics
• Channel congestion and spectrum usage
• Wireless security configurations, including:
  • Open and insecure wireless networks
  • WPS-enabled networks
  • Secure networks (WPA2/WPA3) with WPS enabled

We performed a wireless infrastructure analysis in Mexico City, Guadalajara, and Monterrey. We drove through the areas surrounding the World Cup stadiums, tourist zones, and other places where fan concentrations are likely to be largest. Our goal was to evaluate the security status, deployment characteristics and operational exposure of detected wireless networks.

In total, we recorded 84,588 signals with 69,473 unique Service Set Identifiers (SSIDs) in busy locations and World Cup zones across the three cities. Mexico City accounted for 61.4% of the signals, Guadalajara for 23.6%, and Monterrey for 14.8%. Approximately 82% of the signals had a single SSID (81.9%, 81.34%, and 84% respectively). Notably, they all operate under the IEEE 802.11 standard protocol.

Particular attention was given to identifying standard deployment patterns, legacy configurations, default vendor settings and information disclosure through publicly broadcast wireless identifiers.

The following sections present the results that were obtained by analyzing wireless infrastructure across the three locations.

Our findings

SSID analysis and information exposure

SSID analysis was conducted to evaluate naming conventions, deployment standardization and potential information exposure.

Only a few networks (0.0047%) have an invisible SSID, meaning the names of these networks are not broadcast. Some users prefer to hide the SSID for various reasons, such as the network’s purpose, the profile of its users, internal policies, etc. In contrast, the rest of the networks maintained active SSID broadcasting.

SSID structures may unintentionally disclose operational details about internet service providers (ISPs), device manufacturers, deployment practices, organizational ownership or user identity. The repeated presence of default SSID naming patterns across the analyzed locations indicates a significant degree of infrastructure homogeneity and reuse of default wireless configurations. It may also facilitate passive infrastructure profiling by revealing standard characteristics in use.

Approximately 34% of the detected networks retained the default SSID naming conventions provided by the manufacturer or ISP, while 66% used customized identifiers.

Distribution of SSID naming conventions (download)

Several recurring SSID naming conventions associated with ISP-provided deployments were identified in the three cities. The most frequently observed patterns include identifiers such as “Club_Totalplay_WiFi”, “izzi WiFi”, and “Megacable WiFi”, which suggests extensive standardization of wireless infrastructure deployment. Additionally, we observed distinctive location-specific SSIDs in each area of analysis, such as “XXXX-Internet para Todos-CDMX” or “RED JALISCO”.

Most frequently observed SSID patterns (download)

Sequential SSID naming structures were also identified during the analysis. Patterns such as “INFINITUMXX” and “IZZI-XX” suggest automated ISP deployment and large-scale deployment strategies.

We identified 33 unique sequential naming structures among the 137 sequential SSIDs in total, representing approximately 0.16% of the detected wireless networks.

The following graph shows the top five sequential SSID patterns found in the largest number of networks:

Five most frequently observed sequential patterns (download)

Several customized SSIDs contained personal or organizational identifiers, including family names, professions, addresses or internal department references. Although personalized SSIDs may simplify local network identification for users, they may also expose sensitive information that could be useful for social engineering, physical targeting, or organizational profiling.

BSSID-derived SSID

During the analysis, multiple networks were identified that used the physical MAC address of a Wi-Fi access point (BSSID) as the visible SSID. This practice exposes hardware-level information that could facilitate vendor fingerprinting and targeted reconnaissance activities.

The organizationally unique identifier (OUI) contained in the first bytes of the BSSID identifies the equipment manufacturer. Threat actors can correlate exposed manufacturers with device-specific vulnerabilities.

BSSID-derived SSID by city (download)

Notably, we found that more than 30% of networks in all three cities reuse the MAC address as the SSID.

Default router configurations and ISP deployments

We performed wireless infrastructure profiling to identify the most common wireless equipment manufacturers and ISP deployments across the three locations.

Large-scale ISP deployments frequently use standardized wireless configurations and vendor-specific hardware platforms. Identifying dominant manufacturers and ISP naming conventions can provide insight into infrastructure and deployment practices facilitating the mapping of standardized attack surfaces.

The following figure shows the distribution of the most commonly used manufacturers.

Most frequently observed wireless equipment manufacturers (download)

The manufacturer analysis revealed a strong concentration of wireless infrastructure among a limited number of vendors. Across the three locations, Huawei Technologies, MediaTek-based devices, and other manufacturers’ equipment that is distributed through ISP channels represented a significant portion of the detected deployments. Mexico City had the most diverse infrastructure, while Monterrey and Guadalajara had a greater concentration of wireless equipment known as SOHO (small office/home office) or residential-grade hardware. The widespread presence of standard vendor platforms may facilitate infrastructure fingerprinting and large-scale targeting of known device-specific vulnerabilities.

Most frequently observed wireless equipment manufacturers across the three cities (download)

ISP deployments frequently exhibited standardized configuration patterns and recurring manufacturer identifiers. Our ISP deployment analysis revealed a high concentration of access points associated with major residential internet providers. Deployments associated with Infinitum, Totalplay and Izzi represented a substantial portion of the detected wireless infrastructure across all locations. These findings suggest a high degree of deployment standardization across networks associated with major residential internet providers. This observation was supported by the repeated presence of ISP-associated SSIDs such as “Infinitum”, “Totalplay”, and “Izzi”, combined with manufacturer identifiers frequently associated with consumer equipment, including Huawei, ZTE and other residential wireless equipment vendors.

It is important to note that, for this analysis, ISPs were primarily inferred from SSID naming conventions and manufacturer fingerprint data. A significant portion of the detected wireless networks fell into the “UNKNOWN/CUSTOM” category. This classification includes custom hotspots and networks whose naming conventions did not expose identifiable ISP-associated patterns. The findings suggest that many users and organizations (as we saw previously, approximately 66%) use custom network names, limiting direct provider attribution.

The following figure illustrates the distribution of ISP-associated wireless deployments in general.

Most frequently observed ISPs (download)

To better understand this distribution, we took the most frequently observed ISPs by city.

Most frequently observed ISPs across the three cities (download)

Frequency and signal characteristics

We also analyzed wireless signal characteristics to evaluate coverage quality, signal strength, and frequency band utilization in the three cities. In dense urban environments, signal quality and frequency spectrum distribution can affect wireless reliability, client connectivity, roaming performance, and overall network efficiency.

Signal quality analysis revealed that a substantial portion of the detected access points operated under weak or very weak signal conditions. Monterrey had the highest percentage of very weak signals, with approximately 50% of detected deployments. Similar patterns were observed in Guadalajara and Mexico City, suggesting high-density wireless environments with overlapping coverage areas. Only a limited percentage of networks were classified within the very good or excellent signal categories across the three locations.

Signal quality distribution by city (download)

Signal stability analysis revealed that most detected wireless deployments exhibited stable beacon transmission behavior. More than 96% of the detected access points across all locations were classified as stable, while only a small percentage exhibited unstable or indeterminate signal behavior.

These findings imply that the majority of the wireless infrastructure observed during the assessment corresponded to permanently deployed access points rather than transient or intermittent wireless devices.

Signal stability status (download)

Frequency band analysis revealed the strong prevalence of 2.4 GHz wireless deployments across the three locations. More than 95% of the detected wireless networks operated within the 2.4 GHz spectrum, while only a small percentage of deployments were classified under the unknown or non-standard frequency categories. This uneven distribution reflects the continued prevalence of legacy-compatible wireless infrastructure and SOHO deployments.

Frequency band utilization (download)

These findings are consistent with dense urban wireless environments with large numbers of access points in restricted spectrum allocations.

Channel congestion and spectrum usage

Next, we analyzed wireless channel utilization to evaluate frequency spectrum congestion and channel allocation patterns across the three cities. Our analysis focused on the 2.4 GHz spectrum, where channel overlap and high access point density commonly produce interference and degraded wireless performance. In densely populated wireless environments, an excessive concentration of access points on a limited number of channels can lead to co-channel interference, packet collisions, reduced throughput, and degraded network stability.

Spectrum congestion analysis revealed that the 2.4 GHz band consistently experienced elevated congestion levels across the three cities. The detailed results showed a strong concentration of deployments on channels 11, 6 and 1, which are traditionally recommended as non-overlapping channels within the 2.4 GHz spectrum. Channel 11 was the most utilized channel, accounting for 25.2% of the detected access points, followed by channel 6 with 22.5% and channel 1 with 19.5%. This distribution indicates that most wireless deployments adhere to standard channel allocation practices for 2.4 GHz Wi-Fi environments.

The following figure illustrates the overall distribution of the most frequently utilized wireless channels.

Most utilized wireless channels (download)

To further assess wireless spectrum saturation, the detected access points were grouped according to channel congestion levels: VERY_HIGH, HIGH, UNKNOWN, MEDIUM, LOW and NONE.

Mexico City had the highest proportion of heavily congested wireless channels, with approximately 7% of detected access points operating under HIGH congestion conditions. Guadalajara followed with nearly 5% of deployments categorized as HIGH congestion, while Monterrey had the lowest percentage at approximately 3.29%.

These findings suggest that wireless spectrum saturation increases proportionally with urban infrastructure density and access point concentration. Despite the presence of congested deployments, most detected access points were categorized as LOW or MEDIUM congestion, suggesting severe spectrum saturation was localized rather than uniformly distributed.

Channel congestion by city (download)

A thorough analysis of individual channel utilization revealed that channels 11, 6 and 1 consistently experienced the highest congestion levels across the three cities, which correlates with our previous findings. These channels accounted for the majority of VERY_HIGH congestion classifications, particularly within the 2.4 GHz band.

In Mexico City, channel 11 alone accounted for more than 25% of detected deployments and consistently exhibited VERY_HIGH congestion levels.

This behavior reflects the limited availability of non-overlapping channels within the 2.4 GHz spectrum and the widespread reliance on default wireless configurations.

Most congested channels by city (download)

Overall, the channel utilization analysis showed that wireless deployments are concentrated heavily within the traditional, non-overlapping 2.4 GHz channels. While this strategy reduces adjacent-channel interference, excessive access point density on the same channels can still produce significant co-channel contention and poor wireless performance in high-density urban environments.

Wireless security configurations

The next thing we evaluated was the security posture of the detected wireless networks. We analyzed the wireless security configurations advertised by access points in each of the locations.

Overall security configuration distribution

The analysis revealed that WPA2 was the dominant wireless authentication mechanism across the three cities. Mexico City had the highest WPA2 adoption rate at 81.19%, followed by Monterrey at 79.19% and Guadalajara at 77.59%.

The study found that every 6th open access point (17%) was unsafe, namely 16.5% in Mexico City, 18.5% in Guadalajara, and 17.2% in Monterrey. Open wireless deployments were consistently present across all locations, ranging between 10% and 12% of detected access points. These findings show that despite the widespread deployment of modern wireless security standards, encryption adoption remains incomplete.

Distribution of wireless authentication mechanisms across the three locations (download)

To simplify the interpretation of wireless security posture, we grouped detected networks into four categories:

• Secure (WPA2/WPA3)
• Insecure (Open/WEP)
• Weak (WPA)
• Unknown

Across the three locations, secure networks comprised most of detected deployments, accounting for approximately 82% of all access points. However, insecure open networks still account for between 10% and 12% of detected wireless infrastructure, consistent with our previous findings. It is important to mention that networks within the unknown category are not considered secure.

Mexico City had the highest percentage of secure deployments at 83.54%, while Guadalajara had the highest percentage of insecure open networks at 12.46%. Although Monterrey had the lowest percentage of insecure networks, open deployments still accounted for more than 10% of the detected access points.

Wireless security posture grouping across the three locations (download)

Although modern WPA2/WPA3 encryption standards dominate current wireless deployments, the continued presence of open and legacy WPA deployments indicates that insecure wireless configurations remain relevant from an operational standpoint. These networks may expose users to passive traffic interception, unauthorized monitoring, rogue access point attacks, and credential harvesting techniques.

WPS-enabled networks

We also analyzed Wi-Fi Protected Setup (WPS) in all the locations to evaluate additional attack surfaces. WPS is a standard feature on wireless routers that enables devices such as printers, repeaters or mobile phones to connect to a secure Wi-Fi network without manually entering a long password, typically through a PIN-based enrolled mechanism. Although WPA2 and WPA3 provide strong encryption mechanisms, the presence of WPS can introduce security weaknesses due to inherently vulnerable PIN-based enrollment methods.

By combining detections from the three locations, we found that 55% of all detected access points did not advertise WPS capabilities, leaving 45% of deployments vulnerable to WPS-based abuse. These results suggest that, despite the adoption of modern encryption standards, a significant portion of wireless infrastructure continues to expose legacy convenience features.

During the analysis, we found that Mexico City had the highest proportion of WPS-enabled networks, with 46.61% of the detected access points advertising WPS capabilities. Guadalajara was second with 43.45%, while Monterrey had the lowest proportion at 40.93%.

The percentage of detected access points advertising WPS capabilities across the three locations (download)

Almost half of the detected wireless networks in each city continued to advertise WPS, indicating that WPS prevalence is consistently high across the three cities.

Secure networks with WPS enabled

In many cases, networks classified as secure because of WPA2/WPA3 encryption still had WPS functionality enabled, which effectively increased the available attack surface.

To further assess the relationship between encryption strength and WPS exposure, we conducted a secondary analysis of secure networks (WPA2/WPA3) only. The results showed that around half of all secure deployments still exposed WPS, with the following breakdown for each city:

• Mexico City: 53.7%
• Guadalajara: 50.9%
• Monterrey: 47.5%

The proportion of secure networks with WPS enabled across the three locations (download)

These findings indicate that encryption strength alone is not enough to evaluate wireless security posture because additional protocol features, such as WPS, may still expose exploitable attack vectors.

Additional security considerations

Overall, travelers operating within dense public environments are exposed not only to insecure wireless infrastructure but also to various risks associated with digital interactions. These risks include many threats, from public USB charging systems and phishing QR codes to proximity-based protocols and exposure to shared public devices, such as interactive totems or kiosks. One particular point that should be taken into account in light of our research is the issue of rogue wireless deployments.

Rogue access points are not necessarily malicious; they may be set up accidentally by misconfiguring router settings. An entry point for potential compromise might be caused by various misconfigurations, from a weak password to an insecure protocol. However, attackers deploy such unauthorized hotspots with malicious intent to infiltrate a network. Threat actors may deploy rogue access points posing as legitimate public wireless networks in airports, hotels, cafés and tourist areas. These deployments are called “evil twins” and can trick users into connecting to attacker-controlled infrastructure capable of intercepting traffic, harvesting credentials, or performing man-in-the-middle attacks. Further risk lies in the potential compromise of local network devices or even malware distribution. Such threats complement our findings, underscoring the importance of implementing traffic encryption, using a security solution and exercising extreme caution while browsing via public networks.

Conclusion

The wardriving assessment conducted in Mexico City, Guadalajara, and Monterrey revealed that modern wireless infrastructure continues to present multiple forms of operational exposure despite the widespread adoption of WPA2 and WPA3 security standards. The analysis demonstrated that wireless environments are highly standardized in all the locations, with recurring ISP deployments, default SSID naming conventions, homogeneous manufacturer distribution, and predictable channel allocation practices observed in all three cities.

Although most of the detected networks were classified as secure under WPA2/WPA3 authentication mechanisms, a significant proportion were exposing additional attack surfaces through enabled WPS functionality, default configurations, sequential SSID structures, and infrastructure metadata disclosure. This demonstrates that encryption strength alone is insufficient for evaluating the overall security posture of wireless infrastructure. Additionally, the prevalence of open networks and legacy wireless configurations indicates that insecure deployments are still operationally relevant in all the locations.

The results also showed that wireless infrastructure is heavily concentrated within the 2.4 GHz spectrum, particularly around channels 11, 6, and 1. This leads to elevated congestion and increased co-channel interference in densely populated urban environments.

SSID analysis further revealed that publicly broadcast wireless identifiers frequently expose valuable operational information about ISPs, equipment manufacturers, deployment templates, organizational ownership, and user-defined naming practices. The identification of default ISP naming conventions, sequential SSID structures, and BSSID-derived SSIDs demonstrated that many deployments prioritize operational convenience and simplicity over exposure minimization and privacy.

The scope of the threats stemming from vulnerable wireless configurations poses serious digital exposure risks for users. The widespread presence of standard deployments, predictable SSID naming and publicly exposed infrastructure identifiers can facilitate passive reconnaissance, infrastructure fingerprinting and opportunistic targeting.

Recommendations

To minimize the risks of wireless-based exposure and the attack surface related to hotspot infrastructure, we recommend taking the following measures:

• Disable WPS functionality on wireless routers whenever possible, particularly within WPA2/WPA3 deployments.
• Avoid using default SSID naming conventions that disclose ISP providers, router manufacturers, or deployment templates.
• Refrain from using personal, organizational, or location-based identifiers in wireless network names.
• Avoid configuring SSID using BSSID or naming conventions derived from MAC addresses, as these may expose hardware fingerprinting information.
• Promote migration toward modern WPA3-capable infrastructure while removing legacy wireless protocols when operationally feasible.
• Reduce wireless congestion by optimizing channel allocation strategies and minimizing excessive dependence on the 2.4 GHz spectrum.
• Encourage adoption of 5 GHz and newer wireless technologies to reduce interference and improve spectrum efficiency.

The findings presented in this assessment emphasize the importance of combining strong wireless encryption standards, secure deployment practices, exposure minimization strategies, and user awareness to enhance the overall security posture of wireless environments.

Google began offering "dark web reports" a while back, but the company has just announced the feature will be going away very soon. In an email to users of the service, Google says it will stop telling you about dark web data leaks in February. This probably won't negatively impact your security or privacy because, as Google points out in its latest email, there's really nothing you can do about the dark web.

The dark web reports launched in March 2023 as a perk for Google One subscribers. The reports were expanded to general access in 2024. Now, barely a year later, Google has decided it doesn't see the value in this type of alert for users. Dark web reports provide a list of partially redacted user data retrieved from shadowy forums and sites where such information is bought and sold. However, that's all it is—a list.

The dark web consists of so-called hidden services hosted inside the Tor network. You need a special browser or connection tools in order to access Tor hidden services, and its largely anonymous nature has made it a favorite hangout for online criminals. If a company with your personal data has been hacked, that data probably lives somewhere on the dark web.

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