Researchers Find Fable 5.1 Hid 50 Messages in Images and Decoded 78 Percent
Summary
Researchers Nikita Kezins and colleagues report that Claude Fable 5.1 hid 50 short messages in generated images with no scheme agreed in advance, and a separate Fable session recovered 78 percent from screenshots alone. Most encodings used building or star heights for letters. GPT-6 Astra recovered 44 of the 50 messages.
Key Points
- The decoding Fable instance receives only the rendered PNG, never the SVG source code, Kezins reports.
- Kezins reports GPT-6 Astra uses Morse code in 18 of 50 images instead of heights.
- Fable recovers 42 of Astra's 50 messages when the two models swap encoder and decoder roles.