Anthropic's Claude Mythos Preview found weaknesses in key cryptographic algorithms, including a better attack on HAWK, a post-quantum signature scheme that human experts had reviewed for more than two years. The model found it in just 60 hours at an API cost of about $100,000. The findings don't affect systems in use today, but they show how AI could challenge core assumptions behind internet security, Anthropic says.

Anthropic researchers find weaknesses in cryptographic algorithms with Claude Mythos Preview

Claude Mythos cut HAWK's key strength in half in 60 hours and improved attacks on reduced AES by 200-800x. No production systems are affected. Each discovery cost ~$100K.