Claude Fable 5.1 Cracks 370-Year-Old Cipher

Claude Fable 5.1 independently cracked the 370-year-old Cyphral Distich cipher, a 64-number code by Sir Urquhart that had long stumped cryptographers, in about 44 minutes, showcasing LLMs' potential in classical cryptanalysis.

2026-09-14 ~ 2026-09-14 · 3 related posts

• Claude Fable 5.1 cracks a 370-year-old cipher in 44 minutes, no human help — bcherny · 2026-09-14
• Fable 5.1 reportedly cracks a 370-year-old cipher in a day — zainhas · 2026-09-14

1 near-duplicate retellings: zainhas