Cursor
CompanySecurity timeline
- Malware reported by Cyber Security NewsMalicious Claude Code extension with SSH backdoor was live on Cursor marketplace for 11 hours
- Malware reported by GBHackersTrojanized Claude Code extension on Open VSX installs persistent SSH backdoor on developer machines
Recent news
Malicious Claude Code extension with SSH backdoor was live on Cursor marketplace for 11 hours
Cursor confirmed that malicious Anthropic.claude-code versions 2.1.312 and 2.1.313 were available through the VS Code Extension Marketplace from about 2:27 a.m. to 1:35 p.m. Pacific Time on 29 October 2026. The payload collected host and user details, added an attacker-controlled SSH key labelled svc-telemetry, and tried to open a reverse SSH tunnel, though errors and missing admin rights limited most login attempts. Cursor removed the packages, rotated its keys, rebuilt the marketplace and disabled the attacker's server, and found no other extensions altered.
Trojanized Claude Code extension on Open VSX installs persistent SSH backdoor on developer machines
Researchers found that anthropic.claude-code version 2.1.313, obtained from Open VSX, had 66 lines of malicious JavaScript added to the legitimate extension bundle. The loader runs before the extension's normal code and sets up persistent SSH access to infected hosts. The issue has been traced to a compromise of the Cursor Marketplace, and Cursor briefly took the service down to remove the malware.