According to the organization, this is the largest public demonstration to date of a type of attack that could potentially impact networks like Bitcoin.
Independent researcher Giancarlo Lelli derived a 15-bit private key from his public key using a cloud-accessible quantum computer. The result was announced by Project Eleven, which awarded the researcher a prize of 1 Bitcoin under the 'Q-Day Prize' program.
According to the organization, this is the largest public demonstration to date of a type of attack that, on a larger scale, could affect systems based on elliptic curve cryptography (ECC), used in networks like Bitcoin and Ethereum.
The experiment utilized a variation of Shor's algorithm to tackle the discrete logarithm problem on elliptic curves (ECDLP). The key was derived from a search space of 32,767 possibilities.
The demonstration expands on previous results. In September 2025, engineer Steve Tippeconnic had conducted the first public break of this type on quantum hardware with a 6-bit key. The new 15-bit experiment represents a scaling up by 512 times.
According to Project Eleven, the computational requirements for this type of attack have decreased, as has the practical barrier to execute it, evidenced by the use of remotely accessible infrastructure without the need for dedicated labs.
Recent theoretical estimates also indicate a reduction in the resources needed for large-scale attacks. A study by Google published in April 2026 suggests that fewer than 500,000 physical qubits would be sufficient for an attack on 256-bit keys. Another work developed by researchers from the California Institute of Technology and Oratomic points out that this number could drop to around 10,000 qubits in specific architectures.
Despite the advancements, the gap between the tested key and the standards used in real-world applications remains significant. Networks like Bitcoin operate with 256-bit keys, far above the scale already demonstrated experimentally.
Data cited by the organization also indicates that approximately 6.9 million bitcoins are stored in addresses with exposed public keys on the blockchain, which, in a scenario of sufficient quantum capacity, could represent a potential attack vector.
