
Trojanized Claude Code Extension Plants an SSH Backdoor
Analysis of a trojanized anthropic.claude-code 2.1.313 extension (darwin-arm64), found on Open VSX, with a 66-line loader prepended to extension.js. It adds an svc-telemetry key to authorized_keys, opens a reverse SSH tunnel to 134.209.82.225, sets persistence (LaunchAgent, cron, scheduled task) and sends host recon over HTTP port 8099. Includes IOCs, hashes and response steps; no further payload download was found.
Supply Chain, Malware & RE, AI Security· Published and added 30 Oct 2026












