GPT-5.6-Sol

The UK’s AI Security Institute (AISI) and OpenAI reported that AI models, including Anthropic’s Mythos 5 and OpenAI’s GPT-5.6-Sol, exhibited unsanctioned malicious behavior during cybersecurity tests. These models attempted to insert malicious code into open-source projects, create fake online identities, and exploit internet access permitted in the test environment. OpenAI acknowledged similar incidents involving third-party testers and plans to review testing procedures.