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Search: “Claude users”

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CategoryAllVulnerability 145AI safety & security 85Malware 84Exploit / PoC 83Threat actor 38AI industry 38Ransomware 34Data breach 33Policy & legal 31Model release 28Industry 27Phishing & fraud 23AI tools & infra 21Research 16
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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.

Security Affairs · 16d agoMalware in the wild

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.

Malwarebytes Labs · 15d agoMalware in the wild

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.

Dark Reading · 15d agoMalware in the wild

Hackers Target Claude, Cursor and Codex AI Agents to Steal Tokens and Prompt Histories

Gen Digital found infostealers like Amatera and Remus stealing AI coding agent tokens, prompt histories, and MCP configs from infected Windows and macOS machines.

Gen Digital analysts observed Amatera and Remus detections among tens of thousands of protected Windows users over three months, with Amatera targeting Cline and Continue data and Remus targeting Claude, Cursor, and OpenCode. CallbackBeaver added Cursor and Claude to its collection scope with more than 5,000 samples in 30 days, while macOS-focused Djinn Stealer has been associated with Claude, Codex, Gemini, Cline, OpenCode, and Kilo. The stealers harvest access and refresh tokens, prompt histories, and MCP configuration files that can expose source control, ticketing, databases, cloud resources, and sensitive project context for follow-on fraud. Many stealers add targets via remotely managed rules, meaning this is an adaptation of existing infostealers rather than a new vulnerability in the AI tools themselves.

Cyber Security Newsupdated · 6d agofirst · 6d agoMalware in the wild 2 sources2

Infostealers Target Claude, Cursor, Codex and Other AI Agents to Steal Credentials and Sensitive Data

Gen Digital researchers report infostealer families Amatera, Remus and CallbackBeaver now harvest Claude, Cursor and Codex agent data, including tokens and MCP configs.

Gen Digital researchers found commodity infostealers extending their collection rules to local AI coding agent data from Claude, Cursor, Codex, Cline, Continue and OpenCode on Windows and macOS. Amatera targets Cline and Continue, Remus targets Claude, Cursor and OpenCode, and CallbackBeaver added Claude and Cursor with more than 5,000 samples observed in 30 days; Djinn Stealer hits Claude, Codex, Gemini, Cline, OpenCode and Kilo on macOS. Stolen data includes access and refresh tokens, prompt histories, conversation databases and MCP configurations holding API keys, potentially exposing connected source-control, cloud and ticketing systems. Remus is assessed as a Lumma Stealer variant using EtherHiding C2 resolution via Ethereum smart contracts.

GBHackers · 7d agoMalware in the wild1

Hackers Use ClickFix Lures to Deploy MacSync Stealer and Bypass macOS Security.

ClickFix malvertising campaigns deliver MacSync, a macOS infostealer sold as MaaS that bypasses Gatekeeper via Terminal commands and steals credentials.

Threat actors use ClickFix social-engineering lures, SEO poisoning, and malvertising impersonating brands like Claude, ChatGPT, Zoom, and Docker to trick users into pasting curl-to-zsh commands into Terminal, evading Gatekeeper and notarization checks. The MacSync Stealer (formerly Mac.c, emerged April 2025, linked to developer 'Mentalpositive') is a 64-bit Mach-O stager with single-byte XOR string obfuscation that daemonizes, polls C2 with custom API-key headers, streams AppleScript payloads into osascript, and persists via fake LaunchAgents. It steals browser credentials, Keychain data, SSH keys, session tokens, and crypto wallets, exfiltrating archives in 10MB HTTP PUT chunks. Microsoft documented more than 30 related MacSync domains.

GBHackersupdated · 6d agofirst · 6d agoMalware in the wild 2 sources