Researcher Claims 1 Bitcoin Bounty for Successfully Executing Largest Quantum Attack

The threat of quantum attacks on bitcoin's underlying technology has become more tangible. Quantum security startup Project Eleven recently awarded a 1 bitcoin bounty, valued at approximately $78,000, to independent researcher Giancarlo Lelli for breaking a 15-bit elliptic curve key on publicly accessible quantum hardware. This achievement marks the largest public demonstration of its kind, posing a potential threat to bitcoin, ether, and other major blockchains. Elliptic curve cryptography, which enables crypto wallets to prove fund ownership without revealing private keys, is vulnerable to quantum computers running Shor's algorithm. Although Lelli's result does not immediately compromise bitcoin's 256-bit elliptic curve security, it signifies a significant step forward in quantum attacks on real-world cryptography-based products. The previous public break was a 6-bit demonstration, and Lelli's 15-bit result represents a 512-fold increase in just seven months. Theoretical estimates suggest that the resource requirements for a full 256-bit attack are decreasing rapidly, with some predictions placing the cost below 500,000 physical qubits. This raises concerns for wallets with publicly visible keys, estimated to hold around 6.9 million bitcoin. In response, bitcoin developers have proposed migration plans, including the introduction of quantum-safe address types, while other cryptocurrencies like Ethereum and Ripple are also developing post-quantum transition strategies.