Anthropic gates Claude Mythos Preview after step-change cyber results
Anthropic reported that Claude Mythos Preview found and exploited serious real-world vulnerabilities, while restricting the model to a gated defensive research program rather than general release.
TOWARD DOOM60confidence 86/100
Why it moved the index
Verified real-world vulnerability discovery and exploit development raise offensive cyber risk, while restrictive deployment and a gated defensive program materially constrain diffusion.
AUDIT TRAIL
Assessment history
- R1Toward 60 · confidence 86
New exact model launch and cyber-capability event; existing model assessment remains unchanged.
11 Aug 2026