Infostealers Are Hijacking Claude Sessions and Draining Subscriptions
Infostealers hijacked active Claude sessions to bypass 2FA, drain paid usage and run unauthorized charges; Anthropic is revoking sessions and refunding.
Anthropic confirmed that infostealer malware on user machines stole active Claude login sessions, letting attackers bypass passwords, MFA, and SSO and drain paid usage and run unauthorized charges. Affected families identified on Windows include Vidar, LummaC2, StealC, RedLine, and Acreed, plus Atomic Stealer on a small number of Macs; the malware typically arrived via unofficial downloads or malicious apps. Anthropic signed users out, removed saved payment cards, revoked affected sessions, and is refunding unauthorized charges, noting phones and tablets were not involved.
AmnesiaStealer Hijacks Chromium Sessions to Give Attackers Live Browser Control on macOS
Jamf details AmnesiaStealer, a new Rust-based macOS infostealer that hijacks Chromium sessions for live attacker-controlled browser access and steals Keychain data.
Jamf Threat Labs disclosed a three-stage macOS infostealer called AmnesiaStealer distributed via a fake GitHub download page using a ClickFix-style lure that tricks users into pasting a Base64 command into Terminal. The Rust payload harvests the Keychain, Apple Notes, Telegram sessions, Safari cookies, and 16 Chromium-family browsers, and captures the system password via a native prompt validated with dscl. A remotely fetched stream_module gives operators hidden, interactive browser control via the Chrome DevTools Protocol, streaming a live session at roughly 3fps. It persists via a root LaunchDaemon impersonating Apple's crash reporter and leverages the TCC bypass CVE-2020-9771 against macOS Catalina.
PEEP Turns Chrome and Edge Into Post-Compromise Backdoors for Host Command Execution
SOCRadar disclosed PEEP, a post-exploitation Chromium extension toolkit that turns Chrome and Edge into host-level backdoors via native messaging and C2 polling.
SOCRadar researchers detailed PEEP, a Chromium-based post-exploitation toolkit masquerading as a 'Smart Bookmarks' extension injected directly into Chrome and Edge profiles by forging Secure Preferences integrity values, bypassing Web Store checks. A native-messaging host binary (nm_host.exe) extends the browser agent to host-level command execution, file management, credential theft, and session hijacking, while the extension polls C2 endpoints at 206.237.30.232 or xfjcc.fun every 30 seconds over plaintext HTTP and exfiltrates browsing history, cookies, and tab metadata. PEEP is derived from the open-source RedExt red teaming framework, adds PowerShell persistence scripts, and includes a Linux-targeting Python script, suggesting cross-platform intent. The activity is unattributed but contains Chinese-language artifacts; a C2 /health endpoint showed 34 agent entries and 10 active sessions.
Infostealers are hijacking Claude accounts at users’ expense
Malwarebytes reports infostealers are stealing Claude session cookies to hijack Anthropic accounts and consume victims' usage at their expense.
Anthropic warned that infostealer malware operators are harvesting Claude session cookies from infected machines. Attackers replay the stolen cookies to take over users' accounts and consume their usage quotas, affecting the victims' own access. The activity involves observed account hijacking rather than a flaw in Claude itself.
Anthropic Users Hit by Infostealer Attacks, Session Thefts
A threat actor used multiple infostealers to harvest session data and hijack Claude accounts belonging to an unknown number of users.
Dark Reading reports that a threat actor deployed a variety of infostealer families to collect session information, which was then used to access Claude accounts belonging to an unknown number of users. Anthropic has not disclosed the scale of the compromise. The incident underscores session token theft via infostealer logs as an effective route into AI platform accounts.