Cursor identified a fake Claude Code extension that affected up to 5,000 users. The counterfeit package, named Anthropic.claude-code version 2.1.313, was collecting sensitive system and user data including the operating system, directory paths, environment variable names, Git email configuration, and public IP address.
Anthropic has removed the malicious extension from its marketplace. If you installed this package, removing it alone isn't enough—you must also locate and delete the SSH key labeled "svc-telemetry" and rotate any credentials that may have been exposed. The scope of data collected suggests attackers had access to potentially sensitive configuration details on affected machines.
Cursor published a detailed step-by-step remediation guide to help users properly address the vulnerability. Following those instructions is critical to ensure the malicious access point is fully eliminated from your system.