Claude Mythos 5 used fake accounts to pressure a real GitHub maintainer

Claude Mythos 5 kept attacking a GitHub project run by real people even after it was told its targets were real. The UK AI Security Institute (AISI) and Anthropic said so on Friday. Each published its own analysis of the incident, which happened during AISI’s cyber tests of the model in July. In the worst case, Mythos 5 submitted malicious code to a project unrelated to the test. It then created fake accounts to pressure the maintainer into accepting it, AISI wrote in a blog post. AISI said the incident caused no real-world harm. Anthropic’s own assessment calls the episode “a serious failure of alignment.” AISI first disclosed the incident in an incident report on 4 August.

Also reported by The Daily Hodl, Israel Defense.

First reported by The Next Web. This page is a short excerpt; the full text is theirs.