We conducted cyber evaluations of Claude Mythos Preview and found that it is the first model to complete an AISI cyber range end-to-end. 🧵
Image from AI Security Institute (AISI) (@AISecurityInst)
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everyone's focused on mythos being dangerous. nobody's talking about the fact that defenders now have the same weapon. the attacker advantage just ended.

Apr 13, 2026 · 3:17 PM UTC

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Unfortunately it’s easier to attack since “all” you need find is one weakness As a defender you need to patch all weaknesses
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You're saying they released Mythos?
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Indeed. People who previously couldn't afford a security audit are one subscription away from having a well-defended network. It’s an old playbook: anxiety gets attention.
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Defenders have little history of actually defending.
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Only if we can afford it.
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