Anthropic's Mythos model has the ability to chain together three, four, or sometimes five vulnerabilities to create sophisticated exploits.

Anthropic's Mythos LLM is so capable at computer security tasks that Anthropic did not release it publicly, instead granting access only to critical software makers.

Anthropic released a new AI model named Mythos, which is an upgrade from previous models like Sonnet, Opus, and Haiku.

The Mythos AI model is able to find zero-day vulnerabilities almost completely on its own with almost no guidance from a human.

Anthropic's testing found that Mythos Preview can identify and exploit zero-day vulnerabilities in every major operating system and web browser when directed by a user.

Vidoc, an external security lab, replicated flagship vulnerabilities found by Mythos using other models like Claude Opus 4.6 or GP 5.4 with appropriate scaffolding.