← Back to Feed

Claude AI Just Cracked a Post-Quantum Test Scheme and Found a Faster 7-Round AES Attack

July 28, 2026 · The Hacker News · Severity: HIGH

Anthropic's Claude Mythos Preview derived an end-to-end key-recovery attack on HAWK-256 (expected runtime ~3h42m on 96-core server) exploiting a previously unused symmetry in the lattice scheme, and achieved a 200-800x speedup for a 7-round AES-128 attack by removing a 256-way guessing step. Neither result affects production systems — HAWK remains a NIST post-quantum candidate and the AES attack targets only 7 of 10 rounds requiring impractical chosen plaintexts.

Key Takeaways

  • Claude Mythos Preview derived a practical key-recovery attack on HAWK-256 with ~3.5 hours runtime on a 96-core server
  • The HAWK attack exploits a previously unused symmetry in the lattice behind the signature scheme
  • AES-128 attack achieved 200-800x speedup by removing a 256-way guessing step from an existing meet-in-the-middle attack
☕ Buy a Coffee