
Anthropic developed Claude Mythos Preview, an AI model that autonomously discovers zero-day software vulnerabilities surpassing human expertise and existing automated tools. It uncovered 27-year-old bugs in OpenBSD and 16-year-old flaws in FFmpeg. Mythos found security weaknesses in major cryptography libraries including TLS and AES-GCM, critical for internet security and DeFi infrastructure. The model operates beyond human audits and automated scanners. Currently shared with 40 tech companies under Project Glasswing, Mythos has not been released publicly.