Security | April 24, 2026
Quantum Bounty Tests Crypto Keys
Project Eleven paid 1 BTC after a researcher used public quantum hardware to break a 15-bit elliptic-curve key, a small test far below the 256-bit cryptography used by Bitcoin and Ethereum.
Independent researcher Giancarlo Lelli used a publicly accessible quantum computer to derive a 15-bit elliptic-curve private key, winning a 1 BTC bounty from Project Eleven.
The post-quantum security startup called the result the largest public quantum attack on elliptic-curve cryptography so far. The test searched 32,767 possible keys using a variant of Shor's algorithm, which targets the math behind the signatures used by Bitcoin, Ethereum, and most blockchains. A prior public demonstration broke a 6-bit key in September 2025. Project Eleven said Lelli's result expands that by a factor of 512.