Ethereum co-founder Vitalik Buterin has identified and proposed a plan to address four areas of the network that he sees as most quantum-vulnerable.
Quantum computing and crypto have been in the headlines recently as concerns mount over Bitcoin and other blockchains’ resistance to quantum-capable supercomputers.
Buterin posted his quantum resistance roadmap for Ethereum on Thursday, stating that the four areas are: validator signatures, data storage, user account signatures, and zero-knowledge proofs.
He said that replacing the current BLS (Boneh-Lynn-Shacham) consensus signatures with “Lean” quantum-safe hash-based signatures would fix that component. The tricky part is picking the right hash function, since this choice will likely stick around for a long time.
“This may be ‘Ethereum’s last hash function’, so it’s important to choose wisely,” he said.
Ethereum Foundation researcher Justin Drake proposed “Lean Ethereum,” a plan to make the network quantum-secure, in August 2025.
Quantum safe data storage and accounts
Regarding data storage, or “blobs”, Ethereum currently uses a system called KZG (Kate-Zaverucha-Goldberg) for storing and verifying data.
The plan is to swap this out for STARKs (Zero-Knowledge Scalable Transparent Argument of Knowledge), which are quantum-resistant. “It’s manageable, but there’s a lot of engineering work to do,” said Buterin.
Related: Buterin outlines 4-year roadmap to speed up and quantum-proof Ethereum
The third challenge is user accounts. Ethereum currently uses ECDSA (Elliptic Curve Digital Signature Algorithm) signatures, which are standard cryptographic keys. The fix is to upgrade the network so that accounts can use any signature scheme, including “lattice-based” quantum-resistant ones.
However, quantum-safe signatures are much heavier computationally and would consume more gas.
“The long-term fix is protocol-layer recursive signature and proof aggregation, which could reduce these gas overheads to near-zero,” he said.
Quantum-resistant proofs are very expensive
Quantum-resistant proofs are extremely expensive to run onchain so “the solution again is protocol-layer recursive signature and proof aggregation,” said Buterin.
Instead of verifying every signature and proof individually onchain, a single master proof or “validation frame” would verify thousands of them at once, keeping costs near zero.
“This way, a block could ‘contain’ a thousand validation frames, each of which contains either a 3kB signature or even a 256kB proof,” he explained.
Buterin also commented on the Ethereum Foundation’s “Strawmap” on Thursday, stating that he expects to see “progressive decreases of both slot time and finality time.”
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