Discovering cryptographic weaknesses with Claude

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• Anthropic researchers used Claude Mythos to hunt for genuine mathematical weaknesses in cryptographic systems, running it for roughly 60 hours at ~$100,000 in API cost.
• Findings: real flaws in HAWK and in a deliberately weakened variant of AES — though the researchers stress “neither of these results has a practical impact on today’s computer systems.”
• Key process insight Willison highlights: models “tend to think it is impossible to solve so they don’t try,” so researchers had to repeatedly redirect Claude away from easy/trivial targets and insist on “proper research to find genuinely hard findings.”
• Takeaway: current models can contribute to real research, but only with sustained human steering toward what counts as a genuinely hard, publishable result — not through unprompted autonomous breakthroughs.