Quantum Risk Blockchain Exposure Hits Five Weak Points, Starknet Already Fixes Two

Quantum computers pose a specific threat to blockchain security by breaking certain mathematical equations that most blockchains rely on. StarkWare's recent technical analysis reveals five identifiable weak points in blockchains, each with its own fix and timeline.

The main danger comes from Shor's algorithm, which can derive private keys from public ones, allowing quantum computers to sign transactions as the owner. This puts almost all blockchain exposure within three categories of cryptography: signatures, encryption, and hashing.

Fortunately, post-quantum replacements for these cryptographic methods already exist, including ML-DSA, SLH-DSA, Falcon-512 for signatures, and ML-KEM for encryption. Hashing requires no new math, as a sufficiently large hash built on SHA-256 or SHA-3 remains secure against quantum attacks.

The five blockchain migration surfaces vulnerable to quantum attacks are keys and accounts, apps and inputs, proving, consensus and cross-chain trust, and network transport encryption. Starknet is cited as an example of a blockchain that has already combined hash-based proofs and upgradeable accounts, making it partially quantum-resistant.