An official Anthropic VS Code extension for Cursor was backdoored for nearly 12 hours, threatening up to 5,000 developers. The malicious version, 2.1.313, was distributed through Anthropic’s official Cursor account and auto-installed on many systems. It installed a persistent SSH backdoor using an attacker-controlled key, enabling remote access across Windows, macOS, and Linux.
Anthropic pushed version 2.1.314 to replace it, but has not yet issued a public warning. Security researchers Kevin Beaumont and Luke Roberts of Phorian confirmed the supply-chain compromise. Cursor stated the extension could access local files, source code, and developer tools due to its IDE-level permissions.
Neither company has explained how attackers gained control of the official account.
Source: Ars Technica · Summarized by HeadlinesBriefing