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

A significant milestone has been reached in the realm of quantum attacks, bringing the theoretical threat to Bitcoin one step closer to reality. Project Eleven, a quantum security startup, 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 breakthrough derives a private encryption key from its public counterpart, marking the largest public demonstration of its kind to date. The attack class has the potential to threaten major blockchains, including Bitcoin and Ethereum. Elliptic curve cryptography, which enables crypto wallets to prove fund control without revealing private keys, relies on the impracticality of deriving private keys from public ones. However, quantum computers utilizing Shor's algorithm challenge this assumption. Although Lelli's achievement does not pose an immediate threat to Bitcoin, which uses 256-bit elliptic curve security, it signifies a substantial leap forward in quantum attacks. 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 for resource requirements have also decreased dramatically, with a recent Google Research paper suggesting that a full 256-bit attack could be achieved 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. 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.