Quantum Computing Threat Looms Large for Crypto, Industry Urged to Prepare

A newly released report commissioned by Coinbase serves as a warning to the crypto industry: although quantum computing does not currently pose an immediate threat to cryptocurrency, the sector cannot afford to delay in preparing for this potential risk. The report, which spans 50 pages and was authored by a prominent advisory board comprising renowned cryptographers and academics, including Dan Boneh of Stanford University, Justin Drake of the Ethereum Foundation, and Sreeram Kannan of Eigen Labs, concludes that the advent of a fault-tolerant quantum computer that could potentially break widely used encryption is a growing concern, and the industry must start preparing now. In recent months, concerns about quantum risk have become more mainstream, with Google researchers suggesting that a sufficiently advanced quantum computer could potentially break Bitcoin's cryptography. Major cryptocurrency ecosystems have begun outlining their responses, with the Ethereum Foundation proposing new digital signature types designed to be safe against quantum computers, while Solana and others are experimenting with quantum-resistant wallet designs. The report emphasizes that current quantum machines lack the power to crack the cryptography underpinning Bitcoin, Ethereum, and other networks, as breaking standard encryption would require significant computational overhead, a milestone still considered a major engineering challenge. Nevertheless, the authors caution against complacency, stating that they have high confidence that a large-scale, fault-tolerant quantum computer will eventually be built, although the timeline is uncertain and 'clearly on the horizon.' This uncertainty is precisely the problem, with estimates ranging from 'a few years to a decade or more' and no reliable way to predict breakthroughs. The urgency is reflected in guidance from the U.S. National Institute of Standards and Technology (NIST), which recommends migrating to quantum-resistant cryptography by 2035, a timeline the report suggests may even prove optimistic. The report advises against waiting for the situation to become urgent, emphasizing that transitions across blockchains, wallets, and exchanges could take years to execute safely. Some assets may be more vulnerable than others; for example, Bitcoin wallets that have already revealed their public keys could be targeted, while those still protected behind hash functions may be safer in the short term. Fortunately, quantum-resistant cryptography (PQC) already exists and is being standardized by NIST. However, the bad news is that it's not an easy swap, as post-quantum digital signatures can be tens to hundreds of times larger than current ones, potentially leading to a significant increase in blockchain data costs and reduced throughput. One estimate in the report suggests that replacing today's signatures with quantum-proof alternatives could expand block sizes by up to 38 times. There are also usability challenges, from migrating millions of wallets to deciding what to do with 'lost' or inactive funds that never upgrade. Rather than a single solution, the report outlines multiple transition strategies, including hybrid systems that combine existing cryptography with post-quantum updates or allow a gradual switch when needed. For now, the authors recommend flexible approaches that avoid sacrificing current security or performance while enabling a rapid upgrade later. The report concludes by emphasizing that the time to begin preparing for the potential threat of quantum computing is now.