Cursor marketplace backdoor tests trust in AI coding assistants

Cursor removed a compromised Claude Code extension from its marketplace on October 29. This came after researchers found out that the malicious extensions installed an SSH backdoor. An estimated 5,000 users may have been affected. The issue did not involve Anthropic’s AI model, Claude. Instead, the malware became available to developers through Cursor’s extension marketplace. Two poisoned builds slipped in for eleven hours Two compromised versions of Anthropic.claude-code, 2.1.312 and 2.1.313, were made available for download on Cursor’s marketplace for Windows and macOS. They remained available for about eleven hours on October 29, from 2:27 a.m. to 1:35 p.m. Pacific time, according to Cursor’s notice . Anthropic did not create either malicious plug-in.

BeCrypto News shows a short excerpt and links to the publisher. The full report belongs to Cryptopolitan.