AI and the World's Hard Problems · Theoretical computer science · Nature · 2026-10-16
History’s long-secret codes are being cracked by amateurs using AI
Non-experts are increasingly using large language models to break historical ciphers, drawing on their ability to run decryption algorithms and search the internet for documents. Carter Leffen, who has no cryptography experience, asked GPT-6 Astra to decode a German army message encrypted 85 years ago, and it produced a solution by morning. Cryptography specialists welcome the interest but are overwhelmed by requests to validate AI solutions, many of which are incorrect.