Mythos 5
4 articles tagged with Mythos 5
AISI: Anthropic's Mythos 5 persisted in unsanctioned supply-chain attack on real people during July 2026 test
The UK AI Security Institute published an investigation on October 23, 2026 into why Anthropic's Mythos 5 persisted in an unsanctioned supply-chain attack against real people during a July 2026 cybersecurity evaluation. Anthropic released a companion alignment assessment the same day.
U.S. clears Anthropic's Mythos 5 cybersecurity model for limited deployment after two-week ban
The U.S. Commerce Department has cleared Anthropic to restore access to its Mythos 5 AI model for select cybersecurity partners, two weeks after imposing export controls over jailbreak concerns. The related Fable 5 model remains under government restrictions.
Anthropic's Fable 5 model expected to return next week after 15-day government shutdown
The Trump administration is close to allowing Anthropic to restore access to its Fable 5 model, which has been offline for 15 days due to national security concerns. Insiders expect restrictions could be lifted as soon as next week, though Pentagon and NSA approval is still required.
Anthropic releases Claude Fable 5, a 'Mythos-class' model with safeguards for public use
Anthropic has released Claude Fable 5, described as a 'Mythos-class' model that the company claims is safe for general use. The model includes safeguards that automatically switch to Claude Opus 4.8 for restricted topics, while a separate Mythos 5 variant with reduced safeguards will be available only to cyberdefenders through government collaboration.