Google Researchers Lower Estimated Quantum Resources Needed to Break Cryptocurrency ECC
Summary
Google researchers estimate that breaking the 256-bit elliptic-curve cryptography used by cryptocurrencies could require far fewer quantum resources than previously thought. The attack remains beyond current hardware.
Key points
- Google researchers say their circuits address the 256-bit elliptic curve discrete logarithm problem (ECDLP-256) used by cryptocurrencies.
- Their estimates require fewer than 1,200 logical qubits and about 90 million Toffoli gates, roughly 20 times fewer resources than previously estimated.
- The researchers estimate the attack could take minutes on a machine with fewer than 500,000 physical qubits; this remains beyond current hardware.
- Google did not publish the circuits, instead releasing a zero-knowledge proof intended to let independent researchers verify the claims’ mathematical soundness.
- Google has set a 2029 target for transitioning to post-quantum cryptography and urged industry players, including cryptocurrency organizations, to prepare.
Article Details
- Event Type
- Quantum-security research warning that resource requirements for breaking cryptocurrency elliptic-curve cryptography may be substantially lower than previously estimated.
- Impact
- Google researchers estimate that attacking the 256-bit elliptic curve discrete logarithm problem used by cryptocurrencies could require fewer than 500,000 physical qubits and take minutes, but that hardware remains beyond current capabilities. Google did not publish the circuits, instead providing a zero-knowledge proof for independent verification. The findings suggest a potentially shorter preparation timeline for post-quantum security; they do not establish that current cryptocurrency cryptography can be broken with available machines.