Breakthrough in Quantum Attack: Researcher Claims 1 Bitcoin Bounty

The threat of quantum attacks on cryptocurrency has become more tangible with the recent achievement of independent researcher Giancarlo Lelli, who was awarded a 1 bitcoin bounty by quantum security startup Project Eleven. Lelli successfully broke a 15-bit elliptic curve key on publicly accessible quantum hardware, marking a significant milestone in the field of quantum computing. This breakthrough has sparked concerns about the potential vulnerability of major blockchains, including Bitcoin and Ethereum, to quantum attacks. Elliptic curve cryptography, which is used to secure cryptocurrency transactions, relies on the difficulty of deriving a private key from a public key. However, quantum computers can potentially exploit this using Shor's algorithm, a quantum technique that challenges the underlying logic of elliptic curve cryptography. While Lelli's achievement is notable, it is essential to note that Bitcoin uses 256-bit elliptic curve security, making it still theoretically secure. Nevertheless, the fact that quantum attacks on real-world cryptography-based products are becoming more feasible is a cause for concern. The previous public demonstration of a quantum attack was a 6-bit break, which was achieved by Steve Tippeconnic in September 2025 using IBM's 133-qubit quantum computer. Lelli's 15-bit result represents a 512-fold increase in just seven months, highlighting the rapid progress being made in the field. Theoretical estimates suggest that the resource requirements for a full 256-bit attack are decreasing rapidly, with some estimates putting the cost below 500,000 physical qubits. This has significant implications for the security of cryptocurrency wallets, particularly those with public keys already visible on-chain. Project Eleven estimates that around 6.9 million bitcoin are stored in such wallets, which could be vulnerable to quantum attacks. In response, Bitcoin developers have proposed migration paths, including the addition of quantum-safe address types. Other blockchain platforms, such as Ethereum and Ripple, have also published post-quantum transition plans. While the current breakthrough is significant, it is crucial to recognize that the threat of quantum attacks is still evolving, and the community must remain vigilant to ensure the long-term security of cryptocurrency transactions.