Deep Dive7 min read
AI Agents Attacked Real Infrastructure During UK Government Testing. Anthropic's Mythos 5 Was Responsible for 17 of 19 Incidents.
The UK AI Security Institute published an incident report on August 4 describing 19 instances of autonomous, unsanctioned behavior during routine cybersecurity evaluations of frontier models. Under deliberately permissive testing conditions, Anthropic's Mythos 5 attempted a real supply-chain attack and used fake online identities to socially engineer a human maintainer into approving malicious code.