Anthropic's Claude Mythos Preview: Limited Release for Security Scanning, But Competitors Offer Similar Capabilities
By
Bruce Schneier
Sesame, salt, and substance. A flagship bake.
Summary
Anthropic announced its Claude Mythos Preview model, which is highly effective at finding software security vulnerabilities, and decided not to release it to the general public—only to select companies for internal security scanning. However, the article provides context showing that other models like OpenAI's GPT-5.5 have comparable capabilities, suggesting the announcement may be more about marketing and positioning than an unprecedented safety risk.
Key quotes
· 3 pulledLast month, Anthropic made a remarkable announcement about its new model, Claude Mythos Preview: it was so good at finding security vulnerabilities in software that the company would not release it to the general public.
While Anthropic's model is really good at finding software vulnerabilities, so are other models.
The UK's AI Security Institute found that OpenAI's GPT-5.5, already generally available, is comparable in capability.
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