GPT-6 Astra breaks 217-year-old Napoleonic code in six hours
| Source: HN | Original article
GPT-6 Astra breaks a 217‑year‑old Napoleonic cipher in just six hours, showcasing the model’s advanced cryptanalysis abilities.
OpenAI’s latest model, GPT‑6 Astra, has demonstrated a striking new capability in cryptanalysis. Carter Church, an AI engineer at cybersecurity firm SentinelOne, fed the model a single scanned image of a 217‑year‑old Napoleonic cipher and a brief prompt. Within six hours Astra produced a full decryption, constructing its own cryptographic solver, sorting the 1,202‑by‑1,836 plate into rows, identifying duplicate hand‑drawn marks, and even correcting a historical dating error. The revealed text is a message from Napoleon to a general preparing for the 1809 Austrian invasion.
The breakthrough matters on several fronts. First, it shows that multimodal LLMs can move beyond language tasks to tackle complex pattern‑recognition problems that have traditionally required specialist expertise. Second, the speed and autonomy of the solution—building a solver from scratch without human‑provided algorithms—suggests AI could accelerate the study of other unsolved historical ciphers, potentially rewriting parts of the historical record. Third, the same techniques could be repurposed for modern security work, where rapid analysis of encrypted or obfuscated data is increasingly valuable.
What to watch next is how OpenAI and other developers package these capabilities. Astra’s performance may prompt broader releases of multimodal, tool‑building models for research institutions and security teams. Analysts will also be keen to see whether similar approaches can be applied to contemporary cryptographic challenges, and how the industry balances the benefits of accelerated discovery with the risk of automated code‑breaking tools falling into malicious hands. The episode adds to a growing string of AI milestones that are reshaping both historical scholarship and cybersecurity.
Sources
Back to AIPULSEN