GPT-6 Astra Breaks an Old Enigma Message
Executive Summary
AI model GPT‑6 Astra independently cracked an unbroken Enigma ciphertext (Nr. 172, MVUEH) by analyzing available messages, selecting a promising target, and using the repeated place name ROSENOW as a crib. It built Enigma simulator and Bombe software in Python and C++, ultimately deriving the correct key and plaintext.
Intelligence Metadata - Source Publisher: Schneier on Security - Published Date: 2026-09-22T11:02:45+00:00 - Category: research
Original Description: This is pretty amazing: However, the most astonishing thing about this break is that the GPT6 Astra did it entirely on its own. Carter Leffer only directed GPT6 Astra to see if it could break any of the unbroken Enigma messages published on the Crypto Cellar Research web page. After analysing the unbroken messages on the website, it decided that the most promising message was Nr. 172, MVUEH and it also quickly suspected that the plaintext of Nr. 173, SIPVX, might be related to the plaintext...
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