Mythos is Anthropic's most capable AI model, sitting above Claude Opus in their lineup and specifically designed for advanced security testing and vulnerability research.

It can discover decades-old bugs in major operating systems, chain multiple exploits together, and build working attacks that escape both browser and OS sandboxes. In testing, it found a 27-year-old bug in OpenBSD and a 16-year-old vulnerability in FFmpeg that survived millions of fuzzing runs.

The catch? Anthropic isn't releasing it publicly. Instead, they're running Project Glasswing, giving controlled access to major tech companies like Amazon, Apple, Microsoft, and Google so they can find and patch vulnerabilities before attackers do. A single vulnerability scan costs around $50, making it dramatically cheaper than traditional penetration testing.

Most builders won't get direct access. The model is too powerful for general release, but its capabilities are reshaping how companies think about security testing and bug bounties.