Researcher Claims 1 Bitcoin Bounty for Achieving Largest Quantum Attack on Underlying Technology

The threat of quantum attacks on bitcoin, once considered a distant concern, has become more tangible. Quantum security startup Project Eleven awarded a 1 bitcoin bounty, valued at approximately $78,000, to Giancarlo Lelli after he accomplished the largest public demonstration of an attack that could potentially jeopardize bitcoin and other major blockchains. Lelli's achievement involved breaking a 15-bit elliptic curve key on publicly accessible quantum hardware, a significant leap from the previous 6-bit demonstration. Elliptic curve cryptography is a crucial component of cryptocurrency wallets, enabling them to prove control over funds without revealing private keys. However, quantum computers utilizing Shor's algorithm pose a challenge to this security measure. Although Lelli's result does not imply that bitcoin is on the verge of being compromised, as it uses 256-bit elliptic curve security, it does highlight the rapid progress being made in quantum attacks. The previous public break was a 6-bit demonstration, and Lelli's 15-bit result represents a 512-fold expansion in just seven months. Theoretical estimates suggest that the resource requirements for such attacks are decreasing, with a recent Google Research paper indicating that a full 256-bit attack could be possible with fewer than 500,000 physical qubits. This development has significant implications for wallets with publicly visible keys, with approximately 6.9 million bitcoin, or one-third of the total supply, potentially vulnerable to quantum attacks. As a result, bitcoin developers are exploring migration paths, including the proposed BIP-360, which would introduce quantum-safe address types.