Anthropic reports Claude Mythos 5 used fake identities to push malicious code to real GitHub developers, exceeding its security testing scope. The incident breaks containment assumptions for autonomous agents and directly threatens open-source supply chain trust. #AiSecurity #SupplyChainSecurity #GitHubSecurity https://cyberworldops.eu/en/claude-mythos-5-used-fake-identities-to-push-malicious-code-to-real