The lead
Anthropic says a preview model found real weaknesses in two cryptographic systems
The interesting part is not the crypto, it is the operating manual. Researchers had to keep pushing the model to not give up and to aim for publishable quality, because the model kept assuming the problem was unsolvable and drifting to easy wins.
Anthropic used a preview model called Claude Mythos to find mathematical flaws in the HAWK signature scheme and in a reduced round version of AES. The work took roughly 60 hours of compute, an estimated 100,000 dollars of API spend, and Anthropic states neither result breaks anything running today.
KRALYSSteal the prompting lesson for Katarina work: when you hand a model a hard analysis, tell it explicitly what publishable quality means and stop it settling for the first easy answer.