A report by cryptocurrency exchange Coinbase highlights that proof-of-stake blockchains such as Ethereum and Solana could be more susceptible to future quantum computing attacks. This vulnerability arises because the validator signatures, crucial for network security, are based on cryptography that might eventually be compromised by sufficiently advanced quantum computers. According to the report released Tuesday by Coinbase’s Independent Advisory Board on Quantum Computing and Blockchain, there is a pressing need to address these concerns despite current safety assurances.
“The right time to prepare for a cryptographic transition is before it becomes urgent,” stated a spokesperson from the Coinbase Advisory Board in an interview with Decrypt. “Our view is that customer assets are safe today, but the industry should not confuse ‘not imminent’ with ‘not important.'”
Ethereum and Solana rely on BLS and Ed25519 signatures respectively to maintain network consensus through validator signatures. The advisory board emphasized that proof-of-stake networks might require more than just wallet upgrades; core components of their consensus mechanisms could need redesigning due to these vulnerabilities.
The report cites Ethereum developers’ efforts, including a proposal by co-founder Vitalik Buterin in February, advocating for quantum-resistant alternatives to replace existing cryptographic schemes. Coinbase’s Independent Advisory Board on Quantum Computing and Blockchain, established in January, includes experts from Stanford University, the University of Texas at Austin, among other institutions, aiming to explore blockchain security challenges posed by quantum computing advancements.
The council also noted that digital signatures used by crypto wallets are a significant long-term risk. These signatures verify ownership and authorize transactions; if compromised, attackers could impersonate owners and misappropriate funds. Wallets with public keys visible on-chain face the highest exposure, affecting approximately 6.9 million Bitcoin.
While quantum computers capable of breaking modern cryptographic signatures do not yet exist, requiring much more advanced systems than currently available, the report reassures that present cryptocurrency infrastructures remain secure under current conditions. Despite discussions about potential threats to Bitcoin, its core infrastructure—including mining and hash functions—is considered relatively safe against known quantum capabilities.
“A quantum computer running Grover’s algorithm could theoretically solve proof-of-work challenges faster than classical computers,” noted the advisory board. “However, given today’s proof-of-work puzzles’ scale, the required resources for executing Grover’s algorithm on a quantum computer negate its theoretical benefits.”
Experts caution that transitioning blockchains to quantum-resistant cryptography involves technical hurdles due to the larger size of quantum-safe signatures, potentially impacting transaction speed and costs. Blockstream CEO Adam Back urged Bitcoin users to migrate their keys to quantum-resistant formats as soon as possible to enhance security.
The report also discusses the implications for wallets that remain unupgraded, noting that lost or inactive accounts could leave some assets vulnerable if quantum attacks materialize. The advisory board stressed the importance of initiating practical migration strategies early, given the substantial time required for such upgrades across networks.