Quantum Computing Threatens Bitcoin Sooner Than Expected

Microsoft unveiled its first quantum computing chip, dubbed “Majorana 1.” While the tech community has long speculated about Google’s next-generation quantum effort

Quantum computing has emerged as a potential threat to Bitcoin's security, owing to the cryptocurrency's reliance on public-key cryptography. A recent analysis by a Bitcoin-focused financial platform suggests that a device with 1 million qubits could theoretically crack a BTC address.

As Microsoft advances in quantum computing with the Majorana 1 chip and aims for a 1-million-qubit device by 2027–2029, concerns arise regarding the potential impact on Bitcoin. According to River, a financial platform centered on Bitcoin, 1 million qubits could pose a significant risk to the cryptocurrency.

In a post on X, River explains that while today's quantum computers have around 1,000 qubits, Microsoft's achievements shorten the overall timeline for reaching higher qubit capacities. This, in turn, accelerates the need for Bitcoin developers to make the protocol quantum-resistant.

“When run for several days to weeks, a 1-million qubit QC could potentially crack Bitcoin addresses via a long-range attack. More realistically, we’d need a QC with 13-300 million qubits to carry out a long-range attack in 1-8 hours. If achieved, this would put 5.9 million BTC at immediate risk,” River writes.

Due to Bitcoin's unique setup, which provides direct access to funds once a public key is obtained, the cryptocurrency is more vulnerable to quantum threats compared to banks and other centralized entities that have multiple layers of protection.

“Access to a public key equals access to the money. Traditional banking systems have many layers of protection. Even if quantum hardware were to render https encryption obsolete, a hacker would still need to get past firewalls, authentication protocols, and in-person security checks to breach a bank,” Leishman said.

Highlighting the urgency of the matter, prominent Bitcoin commentator Preston Pysh joined the discussion, asking if the community should “prioritize engineering quantum-resistant addresses” and suggesting BIP-360 (the proposed P2QRH framework).

According to Pysh, the community could potentially implement this through a soft fork, a method that usually allows for backward compatibility while adding new features to the Bitcoin protocol.

“Would the community be better served by prioritizing engineering quantum-resistant addresses? Something like BIP-360 could be soft-forked in as soon as 6 months. Thoughts?” he said in a post on X.

Leishman agreed that securing Bitcoin against quantum attacks is crucial and suggested discussing the issue further within the Bitcoin Core developer community.

“We should be discussing this at length with Core developers. Securing Bitcoin against quantum attacks should be a priority, but we shouldn't rush anything. We need to be building consensus slowly and carefully,” he said.