New research from Google‘s Quantum AI team indicates that a sufficiently advanced quantum computer could derive a bitcoin private key from a public key in approximately nine minutes. This capability, if realized, would allow attackers to hijack transactions before they are confirmed on the network. The findings highlight a significant potential vulnerability in bitcoin’s cryptographic foundations.
The threat extends beyond live transactions. Around one-third of all bitcoin in circulation — including early coins and funds held in addresses where public keys have been exposed or reused — could be stolen without the time pressure of intercepting an active transaction. A powerful enough quantum computer could target these holdings at any point, giving attackers considerable flexibility.
Despite the alarming implications for ownership security, bitcoin’s core mining process would not be directly disrupted by this capability. However, the ability to derive private keys from public keys would fundamentally undermine the network’s guarantees around asset ownership. Control over funds could no longer be considered secure under such conditions.
A notable concern raised by the research is that bitcoin has not yet begun transitioning to post-quantum cryptography, unlike Ethereum, which has already started exploring migration paths. This leaves bitcoin more exposed should quantum computing reach the necessary level of capability. The gap between the two networks on this issue could become increasingly significant as quantum technology advances.
The research does not suggest that such an attack is imminent, as the quantum hardware required does not yet exist at the scale needed. Nevertheless, the findings serve as a warning to the bitcoin community about the long-term risks posed by quantum computing. Developers and stakeholders may face growing pressure to begin evaluating and implementing quantum-resistant cryptographic standards.
Originally reported by CoinDesk.
