Malicious update to Anthropic's Claude VS Code extension on Cursor marketplace ran for nearly 12 hours
- Severity
- High
- Sources
- 1
What happened
A backdoored release, version 2.1.313 of Anthropic's official Claude VS Code extension, was posted to Anthropic's official account on the Cursor extension marketplace, superseding 2.1.312. It was reportedly live for nearly 12 hours and affected at most 5,000 users, who either downloaded it or received it through auto-update, which is enabled by default in Cursor. Anthropic released 2.1.314 several hours after 2.1.313 appeared. Researchers describe this as a supply-chain compromise of the distribution channel. How the account was taken over has not been disclosed, and Anthropic had not notified customers at the time of reporting. Defenders should check for 2.1.313 and move to 2.1.314 or later.
For security analysts · Written by AI from 1 source · Wrong?
What to do
- Check whether the Claude extension in Cursor is version 2.1.313 and remove it if so.
- Update the extension to version 2.1.314 or later.
- Review Cursor's extension auto-update setting if you want to control future updates.
Written by AI from the sources, checked against them
Full story timeline · 1 update
Who reported · 1 outlet
Who and what is in it
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