Researchers Optimize Key Calculation in Shor’s Algorithm, Advancing Quantum Threat to Bitcoin and Ethereum
A collaborative research effort has significantly optimized point addition—a core calculation repeated within Shor’s algorithm—potentially reducing the quantum computing resources needed to break the elliptic curve cryptography securing Bitcoin and Ethereum.
How Shor’s Algorithm Threatens Blockchain Security
Shor’s algorithm is the quantum procedure capable of deriving a private key from an exposed public key. A sufficiently powerful quantum computer running this algorithm could forge digital signatures, effectively allowing an attacker to spend funds from any wallet whose public key is known. Both Bitcoin and Ethereum rely on the secp256k1 elliptic curve, the specific cryptographic target of this research.
Massive Open Challenge Drives Rapid Iteration
The optimization work was conducted through ECDSA.Fail, an open challenge created by Eigen Labs. Over a roughly eight-week period, more than 100 participants—working alongside AI coding agents—submitted over 400 accepted improvements. Each successful optimization became the new baseline for subsequent attempts, creating a rapid, compounding feedback loop.
Human-AI Collaboration Model
The project employed a distinct division of labor: AI agents handled implementation, repeated testing, and smaller-scale optimizations, while human researchers directed high-level strategy and made larger architectural design changes. The accompanying paper does not quantify the exact contribution split between human and machine effort.
Implications for the Quantum Timeline
These findings suggest that the threat to secp256k1 does not solely depend on advances in quantum hardware. Algorithmic improvements alone can reduce the size and capability of the quantum computer required to execute an attack, effectively pulling the timeline forward without any new qubits being built.
Significant Limitations Remain
Despite the progress, the researchers emphasize that they optimized only one major component of the full attack. The current circuit does not include:
- Physical error correction overhead
- The complete Shor calculation
- Hardware-specific costs of execution on a real quantum device
Consequently, no existing quantum computer can use these results to break Bitcoin or Ethereum today.
Read more: Bitcoin and Ethereum race quantum clock as U.S. backs $300 million hardware push
