Malicious npm package steals Claude AI files and leaks attacker’s GitHub token
Security researchers at OX Security uncovered 'mouse5212-super-formatter', a malicious npm package that exfiltrates files from Anthropic Claude’s /mnt/user-data directory to a threat‑actor‑controlled GitHub repo. The package also inadvertently exposed the attacker’s private GitHub token, allowing rapid detection and mitigation. It had over 600 downloads before removal.