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

The threat of quantum attacks on Bitcoin has become more tangible with the latest achievement by Giancarlo Lelli, an independent researcher who has been awarded a 1 bitcoin bounty, equivalent to approximately $78,000, for breaking a 15-bit elliptic curve key on publicly accessible quantum hardware. This breakthrough is considered the largest public demonstration of its kind, posing a potential threat to Bitcoin, Ethereum, and other major blockchains. Elliptic curve cryptography, which enables crypto wallets to prove control over funds without revealing their private keys, is underpinned by complex mathematical logic that is challenged by quantum computers utilizing Shor's algorithm. Although Lelli's achievement does not imply that Bitcoin is on the verge of being compromised, as it uses 256-bit elliptic curve security, it highlights the rapid progress being made in quantum attacks on real-world cryptography-based products. The previous public break was a 6-bit demonstration, and Lelli's result represents a 512-fold increase 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 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. In response, Bitcoin developers have proposed migration paths, including the introduction of quantum-safe address types, while other cryptocurrencies, such as Ethereum and Ripple, have also published post-quantum transition plans.