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Anthropic locks out Claude users after infostealers hijack login sessions

Anthropic invalidated Claude sessions compromised by infostealers such as Vidar, Lumma and Atomic Stealer, which steal browser cookies to bypass 2FA.

Anthropic began locking users out of Claude accounts after infostealer malware stole browser session cookies, letting attackers replay logins and bypass two-factor authentication. Identified malware includes Vidar, Lumma (LummaC2), StealC, RedLine and Acreed on Windows and Atomic Stealer (AMOS) on a small number of Macs. Anthropic signed affected users out, removed saved payment methods and refunded unauthorized charges. One affected user traced the infection to a pirated game downloaded from a Russian underground forum; the company advised victims to remove the malware before resetting passwords and re-enabling 2FA.

Help Net Security · 17d agoData breach in the wild1

Threat Assessment: Egregor Ransomware

Unit 42 assesses Egregor ransomware, a Sekhmet variant likely run by former Maze affiliates using Qakbot, IcedID, and Ursnif for initial access.

Since September 2020, Unit 42 observed Egregor ransomware attacks across the U.S., Europe, Asia-Pacific, and Latin America, coinciding with the Maze team's shutdown announcement. Egregor, a variant of the Sekhmet family, uses commodity malware such as Qakbot, IcedID, and Ursnif for initial access, followed by scripts that modify firewalls, enable RDP, and deploy Cobalt Strike for reconnaissance and exfiltration. A PowerShell script uninstalls the McAfee agent and downloads the Egregor DLL via BITS, executed with the -passegregor10 key. Victims face a three-day ransom deadline before exfiltrated data is published on the Egregor Hall of Shame leak site.

Palo Alto Unit 42 · Aug 17, 2026Ransomware in the wild

Microsoft September 2026 Patch Tuesday fixes 966 flaws, 2 zero-days

Microsoft's September 2026 Patch Tuesday fixes a record 966 flaws, including two Windows zero-days actively exploited to gain SYSTEM privileges.

Microsoft's September 2026 Patch Tuesday addresses a record 966 vulnerabilities, including 105 rated Critical, 81 of them remote code execution bugs. Two zero-days were actively exploited: a Windows Update Stack link-following flaw and a Windows ALPC heap-based buffer overflow, both allowing local elevation to SYSTEM privileges. The ALPC flaw was reported by Volexity and Proofpoint researchers, while the Update Stack flaw was credited to Romain Deperne and the Microsoft Threat Intelligence Centre. Microsoft shared no details on how the flaws were exploited in attacks.

BleepingComputer · 8d agoAdvisory in the wildCVE-2026-69805CVE-2026-58649CVE-2026-69806+27 CVEs1

Suspected Russian Hackers Abuse Google OAuth and WhatsApp Linking to Hijack Accounts

Google tracked three suspected Russian espionage clusters abusing OAuth flows, app passwords, and WhatsApp linking to hijack accounts of diplomats and defense targets.

Google Threat Intelligence Group detailed three suspected Russian espionage clusters, UNC6293, UNC7005 (Storm-2945), and UNC5976, targeting academia, aerospace, defense, governments, and think tanks in Europe, the US, Ukraine, and Armenia. UNC6293, assessed as a sub-cluster of APT29/Ice Relic, conducted OAuth and application-specific password phishing while impersonating State Department officials. UNC5976 registered file-sharing-themed domains hosting fake OAuth login pages and deployed a malicious Excel plugin codenamed HEADRUSH, while UNC7005 abused WhatsApp device linking to hijack accounts and record victims' audio and video.

The Hacker News · 26d agoThreat actor in the wild

Fake Conferences, OAuth and WhatsApp: Inside Russia’s New Espionage Tactics

Google tracks three Russia-linked espionage clusters abusing OAuth, app passwords, and device code phishing against Western researchers and diplomats.

Google's Threat Intelligence Group documented three suspected Russia-linked clusters, UNC6293, UNC7005, and UNC5976, abusing legitimate authentication flows. UNC6293, a likely APT29/ICE RELIC sub-cluster, impersonates US State Department officials in app password and OAuth phishing targeting fewer than five victims at a time. UNC7005, tracked by Microsoft as STORM-2945, spoofs the GLOBSEC conference, runs device code phishing against Microsoft and WhatsApp accounts, and deploys VIDAR and AtomicStealer infostealers. Targets include researchers, academics, diplomats, think-tank analysts, and defense personnel in Europe and the United States.

Security Affairs · 26d agoThreat actor in the wild1

Threat Assessment: Ryuk Ransomware

Unit 42 assesses Ryuk ransomware amid a CISA/FBI/HHS alert on threats to U.S. healthcare, including the UHS attack that disrupted hospital operations.

A joint CISA, FBI, and HHS alert on October 28, 2020 warned of an imminent threat to U.S. healthcare from operators deploying Trickbot and Ryuk ransomware. Universal Health Services reported a Ryuk attack that disrupted all U.S. UHS sites for weeks, with similar incidents at hospitals in Oregon and New York. Ryuk typically arrives after Trickbot or BazaLoader infections delivered via malicious email, and operators enumerate networks with PowerShell and WMI before encryption. The Trickbot Anchor_DNS module performs DNS tunneling for C2, using connectivity checks to benign domains like ipinfo.io and checkip.amazonaws.com.

Palo Alto Unit 42 · Aug 17, 2026Ransomware in the wild