Quoting Anthropic Frontier Red Team
Anthropic Frontier Red Team evaluated several models on 100 randomly selected tasks from its internal Binary Exploitation benchmark, finding that GLM-5.3 develops full control flow hijacks in 4% of the trials; Claude Mythos Preview did so in 6%. The report says earlier models such as Claude Opus 4.6 and GLM-5.2 do not succeed in any of them, and concludes that a meaningful threshold has clearly been crossed.