Coinbase’s Independent Advisory Board on Quantum Computing and Blockchain has released its first position paper on how future quantum computers could threaten today’s blockchains. The board says there is no machine yet that can break major networks, and it likely will take at least a decade to get there, but it argues that chains need to start planning upgrades now.
The paper focuses on the digital signature systems that secure wallets and validator nodes. It warns that powerful quantum computers could eventually forge signatures or steal funds from accounts whose public keys are exposed on-chain. That risk is especially important for proof-of-stake networks, where validators constantly sign blocks.
Algorand and Aptos Are Already Building Quantum Defenses
In its assessment, the board highlights Algorand and Aptos as relatively well prepared for a post-quantum future. Coinbase notes that Algorand has a phased roadmap for quantum readiness and has already executed a quantum‑resistant transaction on mainnet using Falcon, a NIST-selected lattice-based signature scheme.
Algorand also lets users create quantum‑resistant accounts today through logic signatures, without a core protocol change. However, the report says its block proposal and committee voting mechanisms still rely on classical cryptography and will need further upgrades. Even so, the board views Algorand’s live Falcon tooling and state proofs as a strong starting point.
Aptos earns praise for its approach to user accounts. Instead of deriving addresses directly from public keys, Aptos stores the public key as account metadata.
That design means users can switch to quantum‑resistant keys with a simple “authentication key” update transaction, without migrating assets to a new account. Coinbase’s report says this gives Aptos a cleaner path to post‑quantum security once new signature schemes are ready.
Most Major Chains Still Have a Long Way to Go
The advisory board stresses that Algorand and Aptos are exceptions, not the norm. It says many proof‑of‑stake networks, including Ethereum and Solana, face higher quantum exposure because of how their validator signatures and account models work today.
Although both have discussed quantum‑safe upgrades, they will likely require more complex transitions, with users moving funds or rotating keys in large, coordinated waves.
Coinbase’s paper notes that about 6.9 million bitcoin wallets with exposed public keys could become priority targets once quantum computers advance, unless owners move funds in time.
It also says several ecosystems, such as Optimism and Ripple, have published early timelines for hybrid or quantum‑resistant cryptography, but remain in planning and testing phases.
READ MORE: Aptos Price Outlook as Confidential APT Proposal Goes Live
