GPT-6 Astra and Claude Opus 5 cracked two Enigma messages
People directed both attempts. The expert who runs the message archive checked the results.
Two people used AI models to break German Army Enigma messages from 1941 that nobody had solved. GPT-6 Astra broke one that had resisted every attempt since 2005, and Claude Opus 5 broke another. Frode Weierud, who publishes the messages on his Crypto Cellar website, documented both breaks.