GPT-6 Astra Breaks an Old Enigma Message - Devoured - Daily Dev News

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DEVOURED

GPT-6 Astra Breaks an Old Enigma Message

AI security Schneier

OpenAI's GPT-6 Astra independently cracked a previously unsolved Enigma cipher message using custom simulation tools.

What: Using a 'ROSENOW' crib, GPT-6 Astra authored and executed its own Python and C++ scripts to simulate Enigma machines and perform cryptanalysis on message Nr. 172, successfully finding the correct key and plaintext.

Why it matters: This demonstrates an agentic model's capacity to perform multi-step research, write its own tooling, and solve historical cryptographic problems autonomously.

Deep dive

Autonomous Tooling: The model decided which approach to take, wrote the necessary C++ and Python simulators, and performed the brute-force search.
Crib Analysis: The model identified potential links between different messages and used the repeated string 'ROSENOW' to prime its decryption efforts.
Historical Context: The message was part of a set of unbroken Enigma communications hosted by the Crypto Cellar Research site.
Verification: Researchers are currently auditing the model logs to understand the reasoning process behind the successful crack.

Decoder

Crib: A known segment of plaintext that matches a piece of ciphertext, used to crack encrypted messages.
Enigma Bombe: An electromechanical device used by codebreakers to decipher Enigma-encrypted messages.

Original article

GPT-6 Astra Breaks an Old Enigma Message

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 of the unbroken MVUEH message. After trying many different approaches, GPT6 Astra focused on using the repeated place name ROSENOW ROSENOW as a crib. After developing the necessary Python and C++ software for an Enigma simulator and an Enigma Bombe, GPT6 Astra started a thorough break with the ROSENOW crib, which in the end resulted in the correct key and plaintext for the MVUEH message being found.

We are still analysing the GPT6 Astra logs to see exactly how it executed the break. And we are discovering amazing details.

More details at the link.

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