Just to be clear: This did not involve a compromise of any Anthropic systems. A malicious actor used access to Cursor’s marketplace to publish a tampered extension targeting Cursor's users, we were not involved with building, publishing, or hosting this. The versions on our
We identified a security incident affecting a modified Claude Code VS Code extension accessed through our Cursor IDE extension marketplace, impacting at most 5,000 users. This malicious version of the extension was not developed by Anthropic. It does not impact other extensions







