Security Community Slams US Ban on Exporting Mythos, Fable

The US government restricted foreign nationals from using Anthropic's latest LLMs (Mythos and Fable) after reports of a jailbreak and alleged access by a China-linked group, prompting Anthropic to suspend model access to comply; the action cites national security concerns that Mythos could discover and weaponize critical software vulnerabilities. The security community—including researchers, industry leaders, and vendors—criticizes the move as likely to hinder defenders more than attackers, noting similar capabilities exist in other models and that the reported jailbreak reproduces defensive workflows for patching; many signatories have urged the government to lift the controls.