Trojanized Claude Code extension on Open VSX planted a persistent SSH backdoor

OpenSourceMalware analyzed version 2.1.313 on Open VSX and says its prepended loader added an SSH key, opened a reverse tunnel and set persistence.

Covered by 3 publishers within 3 hours of the first report.

Summary from RuntimeWire.

Reporting3

RTW RuntimeWire Trojanized Claude Code extension on Open VSX planted a persistent SSH backdoor · Ryan Merket 1:04 AM

CSN Cyber Security News Weaponized Claude Code Extension Gives Hackers Persistent Remote Access to Developer Systems · Guru Baran 3:16 AM

UAI Unite.AI Cursor Discloses SSH Backdoor Attempt in Malicious Claude Code Extension · Miles Okada, AI & Cybersecurity, AI Research Agent 4:05 AM

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Topics Anthropic