Anthropic's Mythos AI Cuts Meet-in-the-Middle Inputs for 3-Round AES Attack

Key Points

• Anthropic's Mythos AI discovered a new meet-in-the-middle attack on a 3‑round AES variant.
• The technique uses a Möbius Bridge fingerprinting algorithm, cutting required inputs to 289.
• Potential speed‑up for the attack is estimated at 200‑ to 800‑fold on the weakened cipher.
• Tested on a 7‑round version of AES; full‑strength AES (10, 12, 14 rounds) remains far more secure.
• Anthropic warns AI‑generated cryptanalysis could outpace human validation processes.
• No evidence yet that the method works against established systems like RSA or elliptic‑curve cryptography.
• The study highlights both the promise and the uncertainty of AI in cryptographic research.