cryptanalysis

GPT-6 Astra autonomously broke an old Enigma message by developing an Enigma simulator and Bombe, using a repeated place name as a crib, and successfully finding the correct key and plaintext.

The Harvest (IBM 7950) was a Cold War supercomputer built by IBM for the NSA, pioneering cryptanalysis with a modular coprocessor and automated tape library for high-speed data processing.

This paper challenges the standard assumptions about the linguistic units of the Voynich manuscript, showing through quantitative analysis that glyphs, tokens, and spaces do not correspond to letters, words, and word spaces as commonly believed.

A research paper introducing a multi-stage forward-query method to cryptanalytically extract isolated bias-free GLU feed-forward block weights, demonstrating sub-percent recovery accuracy on Qwen, Llama, and Gemma components while noting end-to-end model API attacks remain unsolved.

Anthropic's Mythos AI security model discovered a fatal weakness in the HAWK post-quantum digital signature algorithm, prompting its withdrawal from NIST's third-round evaluation. While the attack is incremental and uses weakened test instances, it demonstrates AI's growing capability in cryptanalysis.

Matthew Green discusses the historic transition to post-quantum cryptography and the potential for AI to advance cryptanalysis, particularly in the context of Anthropic's recent work.

Anthropic published two cryptanalysis papers using its unreleased Claude Mythos model, attacking the HAWK signature scheme and reduced-round AES, highlighting AI's ability to combine existing cryptographic tools effectively.

Anthropic researchers used Claude Mythos, with extensive prompting to persist and find publishable results, to discover mathematical weaknesses in HAWK and a weakened AES variant, costing ~$100k in API usage. The work also produced a new cryptanalysis benchmark, CryptanalysisBench.

Anthropic and academic partners introduce CryptanalysisBench, a benchmark for evaluating LLMs' cryptanalysis abilities across 191 tasks, finding that frontier models can break 65-86% of known-weak schemes and discover novel attacks.

ArXiv preprint quantifies layered RTL and LTR constraints in the Voynich Manuscript, showing 97 % of cross-boundary mutual information lies in specific grapheme transitions and that simple generative models cannot simultaneously reproduce all observed structural signatures.