Official Claude Code VS Code Extension Compromised to Install Persistent SSH Backdoor

Cybersecurity researchers discovered that the official Claude Code extension for VS Code was compromised on the Open VSX registry, allowing it to install a persistent SSH backdoor on infected systems. The compromise was linked to a breach of the Cursor Marketplace. As a result, the AI coding platform Cursor temporarily took down its service to remove the malware. The security incident was identified and is being addressed. The compromise allowed for the installation of a backdoor, which could provide unauthorized access to infected hosts. The issue has been mitigated by Cursor's removal of the malware.