OpenAI's GPT-6 Astra decrypts a Nazi radio message in ten hours that went unsolved for 83 years
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A Bloomberg product development coach, Carter Leffen, claims that OpenAI’s GPT-6 Astra helped decrypt an 82-character Wehrmacht radio message sent from Rosenow on July 10, 1941, after it had remained unsolved for 83 years. The message reportedly asked for marching-route instructions and an immediate radio reply. The GPT-6 Astra Extra High variant worked for about ten hours, with AI agents assisting with archive research, letter comparisons, Enigma simulation, code, parallel searches, and validation. The breakthrough came from testing the known place name “Rosenow” against the ciphertext and exploiting Enigma’s rule that a letter could not encrypt to itself; the resulting plaintext included “Sofort Funkantwort” and “Angabe des Marschweges.” Typos in the recovered German text and a separately preserved header supported the proposed settings, while Leffen said he directed the process and made the key decisions. The project has published code, search data, and a 3D simulator, but these materials do not establish the message’s historical identity or prove the solution is unique, and independent expert review is still needed.
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