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

The threat of quantum attacks on bitcoin has become more tangible after a researcher successfully broke a 15-bit elliptic curve key on publicly accessible quantum hardware, earning a 1 bitcoin prize worth approximately $78,000. This achievement, made possible by Giancarlo Lelli, represents the largest public demonstration of its kind and underscores the growing concern about the potential vulnerability of major blockchains, including bitcoin and ether, to quantum attacks. Elliptic curve cryptography, which enables crypto wallets to prove fund control without revealing private keys, is being challenged by quantum computers using Shor's algorithm. Although Lelli's result does not immediately threaten bitcoin, which uses 256-bit elliptic curve security, it highlights the rapid progress being made in quantum attacks. The previous public break was a 6-bit demonstration, and Lelli's 15-bit result marks a significant 512-fold increase in just seven months. As the cost of launching a full 256-bit attack continues to decrease, the need for migration to quantum-safe address types, such as those proposed in Bitcoin Improvement Proposal BIP-360, becomes increasingly pressing. With an estimated 6.9 million bitcoin, roughly one-third of the total supply, sitting in wallets whose public keys are already visible on-chain, the urgency to address this vulnerability is growing.