Anthropic's VS Code extension was implanted with a backdoor on Cursor for nearly 12 hours
Anthropic VS code extension on Cursor backdoored for nearly 12 hours
An Anthropic VS Code extension was implanted with a backdoor in the Cursor extension marketplace; the malicious version 2.1.313 was present for nearly 12 hours and affected up to 5,000 users. Luke Roberts, CTO and co-founder of security firm Phorion, called it a supply chain intrusion in which attackers took control of Anthropic's official distribution account on Cursor, publishing 2.1.313 and replacing 2.1.312. Independent researcher Kevin Beaumont said Anthropic pushed 2.1.314 several hours later. Cursor and Anthropic have not yet explained how attackers gained control of the account, and Anthropic has not yet warned customers about the matter.
After the official extension distribution account was compromised, Cursor's auto-update, which is enabled by default, allowed the malicious version to spread to as many as 5,000 developers in about 12 hours.