AI Agents Just Slashed the Cost of a Quantum Attack on Bitcoin

In brief

• More than 100 participants working with AI agents reduced the challenge’s resource score from 10.75 billion to 1.496 billion.
• The leading circuit used 1,151 logical qubits and about 1.3 million Toffoli gates, though comparisons with Google’s results carry caveats.
• A later design brought the gate count below 1 million; the results exclude the hardware costs of a full attack.

Researchers working with AI coding agents reduced a resource benchmark for a key step in a potential quantum attack on the cryptography protecting Bitcoin and Ethereum by 86%, according to a paper posted Wednesday.

In other words, they reduced the computing resources needed for uncovering a wallet’s private key, which could let an attacker steal its funds. When quantum computers powerful enough to carry out a full attack will arrive—a milestone known as “Q-Day”—remains uncertain.

“Although its timing remains uncertain, migration away from vulnerable cryptography is already under way,” the researchers wrote. “NIST has standardized post-quantum replacements, and the initial public draft of NIST IR 8547 proposes deprecating classical public-key algorithms at the 112-bit security level after 2030 and disallowing them after 2035.”