A quantum attacker might be able to steal funds from a transaction even before it is fully processed.
Google’s quantum computing team has released a white paper explaining how a sufficiently advanced quantum computer could break the private keys of the 1,000 richest Ethereum wallets in less than nine days, putting more than 20 million ETH at risk.
The paper also outlines a timeline that researchers believe leaves little room for complacency.
Key Findings From Google’s Research
To understand the risk, it is important to know how crypto wallets are secured today. Each wallet has a private key, which functions like a secret password, and a public address that can be shared openly. The cryptographic system used by Ethereum currently makes it practically impossible to derive the private key from the public address. However, powerful quantum computers could completely remove that protection.
According to the report, Ethereum faces vulnerabilities across five different areas. The most immediate risk targets individual wallets, with the top 1,000 holding approximately 20.5 million ETH. Smart contracts, which are automated programs that drive much of Ethereum’s financial ecosystem, are also exposed. Their administrator keys control around 200 billion dollars in stablecoins and other tokenized assets.
In addition, validators responsible for maintaining the network hold about 37 million ETH in staked funds. The infrastructure supporting layer two networks carries further exposure estimated at roughly 15 million ETH.
The threat is not purely theoretical. Google estimates that a powerful quantum machine could break a single wallet’s private key in about nine minutes. When compared to Bitcoin, where a block is confirmed roughly every ten minutes, the implications become clear. A quantum attacker could intercept and steal funds from a transaction before it is confirmed.
Research group Project Eleven refers to this scenario as a mempool attack, a possibility that was previously thought to be far in the future.
Is the Warning Coming Too Late
The paper estimates that such an attack would require either 1,200 logical qubits with 90 million operations or 1,450 logical qubits with 70 million operations, depending on system design. According to Project Eleven, this represents a tenfold improvement over earlier projections.
On the same day, researchers from California Institute of Technology and University of California, Berkeley, alongside Oratomi, published separate findings. Their work suggests that Shor’s algorithm could operate at cryptographically meaningful levels using about 10,000 reconfigurable atomic qubits, potentially breaking ECC 256 encryption within five days on a 22,000 qubit machine.
Even so, experts remain divided on how imminent the threat is. Some analysts believe it is still at least a decade away and will first affect broader internet systems, allowing time for adaptation. Others are already preparing. Google has set a 2029 deadline to upgrade its infrastructure, while Vitalik Buterin has introduced a roadmap aimed at making Ethereum resistant to quantum attacks by transitioning to quantum secure cryptographic methods.#crypto#cryptonews https://coinsignals.net https://t.me/coinsignalpublic
