Anthropic’s proprietary Claude Code CLI tool has had its full TypeScript source code inadvertently exposed through a misconfigured npm package, after a security researcher discovered a leaked .map file referencing the unobfuscated codebase stored on Anthropic’s own cloud infrastructure. On March 31, 2026, researcher Chaofan Shou made the disclosure public, posting: “Claude code source code […] The post Anthropic’s Claude Code Source Code Reportedly Leaked Via Their npm Registry appeared first on Cyber Security News.