Technology
Malicious update reached Anthropic's VS Code extension on Cursor marketplace
Ars Technica reports that a backdoored Anthropic extension potentially reached as many as 5,000 developers, and neither Anthropic nor Cursor has explained how attackers gained account control.
The short version
- Ars Technica reports that an official Anthropic VS Code extension on Cursor's marketplace was backdoored.[Ars Technica]
- Malicious version 2.1.313 was distributed through Anthropic's official Cursor account, affecting at most 5,000 users.[Ars Technica]
- Anthropic pushed version 2.1.314 several hours after the malicious release, according to independent researcher Kevin Beaumont.[Ars Technica]
- Neither Cursor nor Anthropic has explained how attackers gained control of the account, and Anthropic has not yet warned customers.[Ars Technica]
Key facts
- An official Anthropic VS Code extension available on Cursor's marketplace was backdoored, according to Ars Technica.[Ars Technica]
- Malicious version 2.1.313 was distributed through Anthropic's official account on Cursor, according to Kevin Beaumont and the CTO and co-founder of Phorian.[Ars Technica]
- The malicious version reportedly affected at most 5,000 users, presumably through manual downloads or automatic installation.[Ars Technica]
- Anthropic pushed version 2.1.314 several hours after the previous version became available on Cursor, according to Kevin Beaumont.[Ars Technica]
- Phorian CTO and co-founder Luke Roberts described the incident as a supply-chain compromise in which attackers gained access to the official distribution channel.[Ars Technica]
- Neither Cursor nor Anthropic has explained how attackers gained control of the account, and Anthropic has not yet warned customers.[Ars Technica]
What remains uncertain
- The number of affected machines is an upper-bound figure; actual exposure has not been confirmed.[Ars Technica]
- How attackers gained control of Anthropic's account remains unexplained by Anthropic or Cursor.[Ars Technica]
- Whether Anthropic will warn customers directly is unknown; as of reporting, it had not done so.[Ars Technica]
Sources
Outlet counts describe coverage, not independent confirmation. Reports may share a wire service or original source.