OpenAI’s Astra and Anthropic’s Opus 5 used to crack long-unsolved Enigma messages
Developer Carter Leffen says he instructed OpenAI’s newest model, Astra (referred to as GPT‑6 Astra), to search archival databases and successfully recovered the plaintext of an Enigma message that had been unresolved since 2005, a solution later validated by archivist Frode Weirerud. Separately, cryptanalyst Jack Willis reports using Anthropic’s Claude Opus 5 to break a different unsolved Enigma message; Weirerud says seven Enigma messages remain unbroken.