Coinbase’s quantum computing advisory board stated that a sufficiently powerful quantum computer could eventually break the cryptography securing major blockchains. Their report highlighted Algorand and Aptos as networks taking proactive steps toward quantum resistance, while suggesting proof-of-stake chains like Ethereum and Solana may be more vulnerable to such attacks. The board assessed the threat is not imminent but warrants preparation.
Coinbase’s quantum researchers outlined the threat quantum computers pose to blockchains in a published paper. “A sufficiently powerful quantum computer could one day break the cryptography that secures digital assets across major blockchains,” Coinbase said. The board has high confidence such a machine will eventually be built.
The report stated that Algorand has a staged roadmap toward full quantum readiness and has deployed quantum-resistant cryptography. It noted that users can create quantum-resistant accounts without requiring protocol modifications. Algorand recently completed its first quantum-resistant transaction, though block proposals and committee voting remain vulnerable.
Coinbase said Aptos is well positioned for a transition to post-quantum secure transactions. On Aptos, a user’s address isn’t derived from the hash of their public key. Users need only sign a transaction updating their authentication key to a post-quantum public key, with no need to move assets.
The report warned proof-of-stake blockchains, including Ethereum and Solana, may be at greater risk due to validator signature schemes. It acknowledged Solana has created a new signature scheme, allowing users to move tokens to a secure new address. Ethereum has a clear roadmap to address this, including upgrading signatures.
The board suggested networks could instruct users to migrate to quantum-proof wallets. Wallets with quantum-vulnerable assets would be revoked and lost forever. However, the board clarified the threat doesn’t exist yet. A computer threatening crypto would need orders of magnitude more power than today’s machines, likely taking at least a decade to develop.
