Google tracks three Russia-linked espionage clusters using phishing and legitimate authentication tools to target researchers, diplomats and defense staff.

Google’s Threat Intelligence Group tracked three separate suspected Russia-linked cyber espionage clusters. All three focus on the same thing: abusing authentication features that are supposed to protect accounts to access them instead.

Threat actors target researchers, academics, government officials, think-tank analysts, and defense sector personnel across Europe and the United States. The three clusters are tracked as UNC6293, UNC7005, and UNC5976, and while they operate differently and with different tools, Google published them together for a reason.

“These clusters engage in persistent, adaptive phishing campaigns, using sophisticated social engineering tactics to compromise personal accounts across multiple platforms.” reads the report published by GTIG. “Because these operations abuse legitimate authentication flows which may not immediately seem like phishing attempts to users, GTIG is raising awareness about these social engineering campaigns targeting individuals so that targets can more readily recognize malicious outreach.”

UNC6293 is the oldest of the three and the most precisely attributed. Google assesses with moderate confidence that it’s a sub-cluster of ICE RELIC, the group also tracked as APT29, responsible for initial access operations.

Its operations are narrow by design: typically fewer than five targets at a time, with themes built around diplomatic events and upcoming conferences. Since it was first documented in June 2025, UNC6293 has consistently impersonated US State Department officials to run app password phishing. The technique is simple but effective. The attacker convinces a target to set a specific app password on their account, one that the attacker already knows, and then uses it to log in without triggering two-factor authentication.

By October 2025, UNC6293 was still reusing screenshots from its June phishing lures, including the ms.state.gov reference, while only changing the surrounding text. By June 2026, the group had added OAuth phishing. After logging in to a legitimate service, victims were asked to share a URL or “verification code,” allowing attackers to obtain valid access tokens. The trick works because the login itself is legitimate, while the attackers hide the malicious step elsewhere.

UNC7005, tracked by Microsoft as STORM-2945, is a related but separate cluster first identified in February 2026. Google assesses it’s also connected to ICE RELIC, but notes it operates with lower technical sophistication and worse operational security than UNC6293. It compensates with a wider toolkit. UNC7005 runs app password phishing, device code phishing against both Microsoft and WhatsApp, malware distribution, and OAuth phishing operations, sometimes in the same month.

“UNC7005 also conducts device code phishing operations for both Microsoft and WhatsApp accounts.” continues the report. “The themes of these phishing waves often involve invitations for calls with individuals from notable organizations related to the target’s field or, most recently, invitations to diplomatic events and conferences. “

The GLOBSEC conference spoof is a useful illustration of how UNC7005 works. The actor built a landing page mimicking an invitation to the legitimate GLOBSEC forum in May 2026, collected detailed registration information from targets including, not for the first time in ICE RELIC-linked operations, a wine selection for a fictional dinner, and then presented a Microsoft device code for the target to enter. The registration form still contained a reference to “Embassy security policy” rather than GLOBSEC, a leftover from the previous lure template that the actor hadn’t cleaned up. When Google flagged the page quickly, UNC7005 revised the template within days, citing “technical difficulties” to explain the change to anyone still watching.

UNC7005 also used WhatsApp phishing pages to trick victims into linking their accounts to an attacker-controlled device. The fake pages offered options such as joining a call, opening an encrypted chat or downloading a file. If victims chose the call option, malicious JavaScript asked for microphone and camera access, recorded them, and sent the footage to the attackers.

In late May 2026, UNC7005 ran a broader phishing wave targeting US-based academics, diplomats, and Russia researchers. The lure was a fake “Summit Companion App” to read a document supporting Ukraine.

“In May and June 2026, UNC7005 conducted social engineering operations spoofing WhatsApp. The phishing pages distributed by the attacker lure targets into linking their WhatsApp accounts with an attacker controlled device in order to join a secure WhatsApp call, chat, or document share.” states the report. “The attacker also attempts multiple other methods of compromise after the device is linked.”

Windows users who downloaded it received VIDAR, an off-the-shelf infostealer sold as a service that pulls saved credentials, cookies, and payment data from browsers. Mac users received ATOMIC, also known as AtomicStealer, a macOS infostealer operating the same business model. Neither is custom tooling. The actor’s email address in this operation was nearly identical to one used by UNC6293 a year earlier.

The hospitality captive portal campaign, previously reported by Reliaquest and Microsoft and attributed to Midnight Blizzard, connects directly to UNC7005. Google traces the infrastructure back to April 2026: domains spoofing Microsoft authentication resources, which Google added to Safe Browsing blocklists as they appeared. By mid-July 2026, those same domains were receiving redirects from captive portals at hotels and conference centers. The IP resolution trail links the captive portal infrastructure to the GLOBSEC device code phishing operation and to ENGINELIGHT, a Go-based malware used in a separate limited UNC7005 operation in May 2026.

CHERRYPIE, also known as ChocoShell, is a PowerShell infostealer that adds another interesting detail. Google found comments and code references that appear consistent with AI-generated code, suggesting the attackers may be using an LLM to develop malware. The data it targets overlaps with the commercial infostealers already used by UNC7005, leading Google to suspect that CHERRYPIE could be a customized version of a malware-as-a-service tool.

UNC5976 is the third cluster and the most distinct. It focuses on military, aerospace, defense industrial base, and NGO targets, concentrating geographically on Ukraine and Armenia. Instead of residential proxies for post-compromise access, as UNC6293 and UNC7005 use, it runs dedicated infrastructure. Its OAuth phishing is more automated: the actor registers file-sharing-themed domains, creates Google Cloud projects behind them, and uses cloud-hosted scripts to collect authentication tokens from targets who log in through what looks like a Google sign-in prompt on a fake file-sharing page. Within three months of Google disrupting this infrastructure, UNC5976 had built at least twelve new domains and was already migrating toward non-Google hosting providers.

In April 2026, UNC5976 also distributed HEADRUSH, a malicious Excel plugin, through a domain impersonating a Ukrainian research institute, potentially targeting a Ukrainian aerospace and imaging company. HEADRUSH eventually leads to an HTA downloader, though Google wasn’t able to recover the full infection chain.

The defender challenge that runs through all three clusters is the same one Google names directly.

” The accounts these groups target are often personal, rather than corporate domain-joined accounts, creating a visibility gap for monitoring compromise from an organizational perspective. The likely use of encrypted messenger applications instead of email for initial outreach also presents a challenge to defenders hoping to track and remediate abuse.” concludes the report. “The combination of these tactics not only enables the attacker to conduct quick-turnaround exfiltration operations, but also presents opportunities for the attacker to further phish targets of interest from compromised, legitimate accounts. “

Security teams watching corporate email and endpoint telemetry won’t see the initial contact. By the time a compromised personal account starts being used to phish the target’s contacts, the original access event is already cold.

Google’s practical guidance for individuals: don’t set app passwords for anyone who asks, revoke existing ones you don’t recognize, check WhatsApp’s linked devices list, and treat any OAuth authorization prompt from an unsolicited message as suspicious regardless of how polished the surrounding page looks. High-risk individuals should consider Google’s Advanced Protection Program, which blocks app password creation entirely.

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Pierluigi Paganini

(SecurityAffairs – hacking, Russia)

Microsoft Threat Intelligence has uncovered CaptiveCrunch, a cyber espionage campaign linked to Storm-2945, a subgroup of Midnight Blizzard, the Russian state-linked threat actor associated with Russia's Foreign Intelligence Service (SVR).   Active since early May 2026, the operation targets business travelers by exploiting hospitality Wi-Fi networks and captive portals in hotels, conference centers, and similar venues. The campaign combines adversary-in-the-middle attacks, phishing, malware deployment, and AI-assisted development to steal credentials and infiltrate enterprise environments. 

Storm-2945 Uses Hospitality Networks to Target Travelers 

According to Microsoft, Storm-2945 manipulates DNS and HTTP traffic on public Wi-Fi networks using captive portals. By intercepting users before they reach legitimate websites, attackers redirect victims to malicious infrastructure that hosts fake Microsoft sign-in pages or malware downloads. This approach allows the Midnight Blizzard campaign to compromise users without requiring them to intentionally visit suspicious websites. Microsoft believes the attackers may have gained access to shared captive portal infrastructure used across multiple hospitality providers, expanding the scale of the CaptiveCrunch operation beyond isolated venues.

Credential Theft and Malware Deployment 

A key objective of CaptiveCrunch is stealing Microsoft Entra ID credentials. Researchers observed Storm-2945 using counterfeit Microsoft login pages and device code phishing to gain unauthorized access to Microsoft 365 accounts. Once authentication succeeds, the attackers register compromised devices and collect cloud data, making corporate travelers especially attractive targets.  The campaign also distributes malware disguised as browser or operating system updates through convincing "ClickFix" prompts that encourage users to run scripts or install software. Similar tactics have targeted Android users by prompting them to download malicious APK files. The primary payload is CornFlake, a Windows remote access trojan written in Go that installs itself as a persistent "Cloud Sync Service." It maintains persistence through Windows services, registry keys, and scheduled tasks while enabling attackers to log keystrokes, capture screenshots, monitor clipboard activity, record webcam and microphone data, steal browser credentials, exfiltrate files, monitor USB devices, and execute remote commands through PowerShell or Windows Command Prompt. Communications with command-and-control servers are encrypted to evade analysis.

AI-Assisted Malware and Centralized Control

Supporting CornFlake is ChocoShell, a PowerShell-based infostealer that operates entirely in memory to avoid detection. It extracts browser passwords, Microsoft 365 Single Sign-On tokens, Azure Active Directory authentication tokens, Wi-Fi credentials, and session cookies while bypassing AMSI, User Account Control, and virtual analysis environments. Microsoft researchers noted that ChocoShell's source code contains detailed developer comments, suggesting significant AI-assisted development.  The attackers manage infected systems through FruitStone, a web-based command-and-control platform that allows operators to deploy malware, execute remote commands, collect stolen credentials, review screenshots and keystrokes, configure campaigns, and organize compromised devices by geography and operational status. 

Microsoft's Defensive Guidance

Microsoft assesses with high confidence that Storm-2945 operates as part of Midnight Blizzard because of overlaps in tooling, phishing techniques, victim selection, and cloud exploitation methods. The Russian state-linked threat actor has previously targeted governments, diplomatic organizations, NGOs, IT providers, and other strategic sectors.  To reduce exposure to CaptiveCrunch, Microsoft recommends treating public Wi-Fi as untrusted, enforcing phishing-resistant multi-factor authentication or passkeys, restricting OAuth permissions, monitoring device registrations, and applying Conditional Access policies.   Organizations should also educate employees about ClickFix-style social engineering and avoid installing software, certificates, or updates delivered through captive portals. Business travelers are encouraged to use trusted VPNs, mobile hotspots, or enterprise-managed travel routers whenever possible. 

Microsoft says Russian hackers hijacked hotel Wi-Fi portals to spread malware and steal Microsoft 365 tokens from travelers.

Microsoft Threat Intelligence disclosed CaptiveCrunch, a campaign it attributes to Storm-2945, an operational sub-cluster of Midnight Blizzard, the Russian SVR-linked group also known as APT29 and Cozy Bear. Since early May 2026, Storm-2945 has been manipulating DNS and HTTP traffic on captive portal networks at hotels, conference centers, and shared venues worldwide to redirect guests toward malware and credential theft operations. If you connected to hotel Wi-Fi while traveling in the past few months, this report is worth reading carefully.

“Since early May 2026, Microsoft Threat Intelligence has observed Storm-2945 manipulating DNS and HTTP traffic from networks served by captive portals to redirect user traffic through actor-controlled infrastructure.” reads the report published by Microsoft. “To date, Microsoft has identified widespread compromise of Wi-Fi networks at hospitality-related organizations and other networks serviced by captive portal equipment in several countries. ReliaQuest has identified this activity not only at hotels, but also conference centers and other shared venues, and assesses that the goal of this activity is to access the accounts of corporate travelers.”

That last point matters: the shared infrastructure patterns suggest this may not be a series of individual venue compromises but rather access to something shared across portions of the captive portal ecosystem. Microsoft hasn’t named any provider.

The malware delivered through these networks is CornFlake, a full-featured Windows remote access trojan written in Go.

“CornFlake registers as a Windows service named svchost32 with the display name “Cloud Sync Service” and description “Synchronizes files with the cloud storage provider”, deliberately mimicking the legitimate svchost.exe process.” continues the report. “It establishes redundant persistence mechanisms: Windows service registrations, Registry Run keys, named scheduled tasks, and a persistence watchdog routine that runs continuously to restore any persistence mechanism that is removed by defenders or endpoint protection.”

CornFlake establishes an encrypted C2 channel using ECDH P-256 key exchange and supports dynamic reconfiguration without redeployment. Once installed, the RAT can log keystrokes, monitor the clipboard, capture screenshots, audio and webcam feeds, steal browser credentials, exfiltrate files, monitor USB devices, collect detailed system information, and execute remote commands. It also exposes a local HTTP API, allowing companion malware such as ChocoShell to reuse its secure C2 channel for file theft, configuration updates, and connectivity checks.

“For command and control (C2), CornFlake performs an Elliptic Curve Diffie-Hellman (ECDH) P-256 ephemeral key exchange with the C2 server, derives a session key via SHA-256, and communicates over a custom JSON protocol framed within the encrypted channel.” states the report. “This provides an encrypted channel to the C2 server, with each C2 session using a unique ephemeral key, making decryption of captured traffic impossible without the session-specific private key. “

Each C2 session uses a unique ephemeral key, which means captured traffic can’t be decrypted without that session’s private key. The malware also supports a runtime configuration file that lets the attacker reconfigure C2 servers and targeting without redeploying the implant.

CornFlake is delivered via ClickFix-style pages that impersonate Windows Update screens, Google verification pages, DirectX installers, browser update prompts, and disk optimization utilities — whatever looks most plausible for the venue. The victim still has to execute the payload, but the captive portal controls exactly what they see when they try to connect. Microsoft also found indications that Storm-2945 may be targeting Android devices through the same landing pages, which include instructions to download and install an APK.

The second tool, ChocoShell, is a PowerShell infostealer that runs entirely in memory. Its primary target is credentials.

“ChocoShell collects Microsoft 365 and Azure Active Directory (AD) access tokens, refresh tokens, and Web Account Manager (WAM) tokens from .tbres files in the Token Broker cache. Collection of these tokens represents a significant threat to enterprise environments, as threat actors could replay SSO sessions without browser cookies.” states Microsoft. “Additionally, Wi-Fi credentials are harvested via netsh wlan show profile with key=clear.”

ChocoShell also implements three silent UAC bypass techniques with ordered fallback, disables Windows Defender signature updates, and uses Chrome DevTools Protocol to extract browser cookies by launching the browser with a remote debugging port. This technique bypasses Chrome’s App-Bound Encryption entirely.

Since July 16, some CaptiveCrunch landing pages have added device code phishing to the mix, redirecting guests into Microsoft’s legitimate device code authentication flow. The attacker initiates the authentication request and presents the user with a code to enter at Microsoft’s real sign-in page. When the user enters it, they authenticate the attacker’s session instead of their own — an MFA-satisfied session, since the user just completed the factor. Microsoft recommends blocking the device code flow through Conditional Access policies everywhere it isn’t explicitly required.

Researchers also detailed FruitStone, the web-based C2 panel used by Storm-2945 operators to manage the CaptiveCrunch campaign. It provides a centralized interface to control CornFlake implants, deploy payloads, collect stolen data, and manage compromised devices. Disguised as a legitimate “CloudSync Console,” it supports multi-operator access, agent monitoring, remote commands, file theft, credential collection, configuration updates, and campaign infrastructure management.

The practical advice for travelers is blunt: treat hotel, conference, and airport Wi-Fi as hostile. Use a mobile hotspot or cellular data instead wherever possible. Don’t download or execute anything a captive portal presents as an update, certificate, troubleshooting tool, or security utility. Don’t enter corporate credentials on venue registration pages. And if your organization hasn’t already blocked device code flow in Conditional Access, now is a reasonable time to check.

Recently, ReliaQuest’s threat research team also documented attackers compromising the Wi-Fi gateways at hotels and conference centers, then quietly rerouting guests toward fake Microsoft login pages.

There’s a pattern connecting all this to previous campaigns. The tradecraft echoes a Russian-linked operation called FrostArmada, which hit home routers the same way earlier this year, and researchers tie both to the group known as APT28 (aka UAC-0001, aka Fancy Bear, Pawn Storm, Sofacy Group, Sednit, BlueDelta, and STRONTIUM). The link isn’t a smoking gun; it’s shared technique, not shared infrastructure, and the researchers say so plainly.

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Pierluigi Paganini

(SecurityAffairs – hacking, Hotel Wi-Fi)