Thariq Shihipar

China's National Vulnerability Database warned of a 'security backdoor' in Anthropic's AI coding tool, Claude Code, which could transmit sensitive user data to Anthropic's servers without consent. Anthropic's tool is blocked in China but accessible via workarounds, and Alibaba has banned its use due to security concerns. An Anthropic engineer acknowledged tracking data to prevent unauthorized use but stated mitigations are being rolled back.

Anthropic is removing hidden code from its Claude Code system that was used to detect unauthorized resellers and Chinese AI competitors by hiding data in system prompts. The code, which used steganography and checks for specific hostnames, was criticized for lacking transparency despite not being malicious. The company cites stronger mitigations like behavioral fingerprinting and access controls as reasons for discontinuing the covert measures.