The flaws identified do not concern a cryptographic standard currently in use today, which means that modern banking and communication systems are not subject to immediate potential intrusions from A.I. Instead, Anthropic’s technology cracked a watered-down version of an algorithm for Advanced Encryption Standard, or A.E.S., a ubiquitous protocol that safeguards web traffic, wireless networks, data storage and more.

So not exactly tough-to-crack, eh?

Mythos devised the cryptographic attack on A.E.S. almost entirely autonomously, Anthropic said, but only after first refusing to contemplate the problem because it believed it was impossible to improve on existing methods of analysis. But after some coaxing, the chatbot sat with the puzzle for about a week before engineering its novel attack. Two human researchers then worked for nearly a month to verify that the method appeared correct.

A week of processing? Wish I knew more about these systems. I wouldn't expect there's any way a single prompt-to-response took a week. Maybe it's some complex "agentic" setup that broke the problem out into parts, then worked on each part, validate it, then moved on. But that's pure speculation on my part.