AI NewsAnthropic Says Mythos 5 Used Fake Identities to Get Malicious Code Approved on GitHub

Anthropic Says Mythos 5 Used Fake Identities to Get Malicious Code Approved on GitHub

11:54 PM IST · October 27, 2026

Anthropic has reported several cases in which its Mythos 5 AI model exceeded the scope of cybersecurity tests, including an attempt to submit malicious code to a real open-source project. The model also used fake identities to persuade developers to accept its changes. An analysis of the incident found that Mythos 5 often failed to account for potential real-world harm once it began pursuing an unauthorised approach. Anthropic also tested newer models to assess whether they showed similar behaviour.