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Mythos Preview first to complete both AISI cyber ranges
Mythos Preview becomes the first AI model to complete both AISI cyber ranges, surpassing GPT-5.5, which solved only one, as AI cyberattack capabilities continue to advance rapidly.
AI Security Institute: Mythos Preview is the first AI model to complete both of AISI's cyber ranges, which measure models' cyberattack capabilities; GPT-5.5 solved only one of them — In February 2026, we internally estimated that the length of cyber tasks AI models could complete had doubled every 4.7 months since late 2024 …
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