Anthropic's AI Breaks HAWK Digital-Signature Scheme in Record Time

Anthropic's AI model, Claude Mythos Preview, has uncovered a flaw in the proposed HAWK digital-signature scheme. This finding effectively halves its smallest key strength, undermining one of the candidates to replace current web and banking signatures in a post-quantum world.

The AI-driven attack, which cost about 60 hours and $100,000 in computing, reduced the work needed to break HAWK's smallest parameter set from roughly 2^64 to 2^38 operations. This also renders larger key sizes far less attractive.

The results reinforce warnings that classical cryptanalytic attacks are rapidly improving, just as Bitcoin and other networks debate how and when to migrate to quantum-resistant cryptography.