Tampered Claude Code Extension Planted SSH Access on Developer Machines
Photo: TokenPost
Security researcher Paul McCarty (6mile) identified a tampered Anthropic Claude Code extension on Open VSX that added SSH access and persistence to developer machines, with findings limited to analyzed version 2.1.313. The package, listed as anthropic.claude-code@2.1.313, included a 66-line loader placed before the extension’s regular code. McCarty’s analysis found it could run when VS Code launched or a webview opened, without a user starting a Claude conversation. The code wrote an attacker key labeled “svc-telemetry” into the user’s SSH configuration, attempted to enable a local SSH service and opened a reverse tunnel to 134.209.82.225.
Source: TokenPost
