A new study from Google warns that current cryptography in major blockchains is vulnerable to quantum computing attacks with fewer resources than previously believed. The research indicates a quantum computer with under 500,000 qubits could break Bitcoin’s security in about 9 minutes and compromise Ethereum’s 1,000 richest accounts in under 9 days. Experts are urging a swift industry transition to post-quantum cryptography, with Google having set a 2029 deadline for its own migration.
A recent study conducted by Google has revealed quantum computers could break the cryptography securing major cryptocurrencies with far fewer qubits than expected. The research indicates that fewer than 500,000 physical qubits could solve the elliptic curve discrete logarithm problem foundational to blockchains like Bitcoin and Ethereum.
According to the paper’s findings, a quantum computer could crack a Bitcoin private key in approximately nine minutes. This timing aligns closely with the network’s 10-minute block time, enabling a specific “on-spend attack.”
Ethereum‘s account model is also highly vulnerable because it permanently exposes public keys on-chain. The study states the 1,000 richest exposed Ethereum accounts, holding roughly 20.5 million ETH, could be compromised in less than nine days.
Google advises that blockchains should migrate to post-quantum cryptography urgently rather than wait for tangible threats. The Ethereum Foundation has recently published a post-quantum roadmap as noted in the report.
Ethereum co-founder Vitalik Buterin has emphasized the need for changes across validator signatures, data storage, accounts, and proofs. Crypto entrepreneur Nic Carter recently observed that Bitcoin core developers have been the slowest to respond to such cryptographic challenges.
Google has marked 2029 as its deadline for post-quantum cryptography migration. The company’s timeline suggests the quantum threat horizon may be nearer than the industry assumes.
Experts recognize the necessity for preventive steps to maintain blockchain security and stability. Stakeholders are urged to prioritize developing and applying post-quantum cryptographic measures.
