Breakthrough in Quantum Attack: Researcher Claims 1 Bitcoin Bounty

The threat of quantum attacks on cryptocurrency has become more tangible with the latest breakthrough by independent researcher Giancarlo Lelli, who has been awarded a 1 bitcoin bounty for breaking a 15-bit elliptic curve key on publicly accessible quantum hardware. This achievement demonstrates a 512-fold increase in the scale of the attack compared to the previous public demonstration in September 2025. The bounty, worth approximately $78,000, highlights the growing concern over the potential vulnerability of major blockchains, including Bitcoin and Ethereum, to quantum attacks. Elliptic curve cryptography, which underlies the security of these systems, relies on the difficulty of deriving a private key from a public key. However, quantum computers utilizing Shor's algorithm pose a significant challenge to this assumption. While Lelli's result does not immediately compromise the security of Bitcoin, which uses 256-bit elliptic curve security, it underscores the need for the development of quantum-resistant cryptographic protocols. Theoretical estimates suggest that the resource requirements for a full-scale quantum attack are decreasing rapidly, with some predictions indicating that a 256-bit attack could be feasible with fewer than 500,000 physical qubits. This has significant implications for wallets with publicly visible keys, with approximately 6.9 million bitcoins potentially at risk. In response, developers are exploring migration paths to quantum-safe address types, including the proposed Bitcoin Improvement Proposal BIP-360.