Cardano founder Charles Hoskinson accused Ethereum co-founder Vitalik Buterin of undermining quantum-resistant cryptography with speculative warnings about AI-driven mathematical breakthroughs. In an Oct. 9 post, Hoskinson challenged Buterin's skepticism toward lattice-based cryptography. Hoskinson argued that decades of security research had already accounted for the technology's known weaknesses. Hoskinson warned that encouraging developers to abandon established approaches could slow protections already being deployed across internet infrastructure, leaving systems exposed to future quantum attacks.
Buterin warned that AI-assisted mathematical discoveries could weaken cryptography designed to resist quantum computers. Buterin said Ethereum's long-term "lean" roadmap has moved toward hash-based signatures and proofs, avoiding lattice-based designs. Hoskinson rejected that reasoning and accused Buterin of being too invested in Ethereum's existing research direction to reconsider the approach. The dispute concerns post-quantum alternatives to the elliptic-curve signatures used by Bitcoin and Ethereum.
Buterin's concern draws partly on integer factorization, where mathematical advances such as the general number field sieve dramatically improved techniques for attacking RSA encryption. Buterin suggested that AI could compress decades of comparable mathematical progress into a much shorter period, potentially revealing unexpected shortcuts against lattice-based systems. Hoskinson characterized the case against lattices as a hunch about mathematical structure based on the general number field sieve's history. Hoskinson said the number field sieve emerged from techniques involving arithmetic relationships and smooth numbers. Hoskinson said no comparable mechanism has been demonstrated against the lattice problems underpinning modern post-quantum standards.
Hoskinson cited more than four decades of research, including advances in lattice reduction and sieving algorithms. Hoskinson said those advances progressively improved attacks without producing a general breakthrough capable of defeating properly configured systems. The US National Institute of Standards and Technology standardized ML-KEM for key encapsulation and ML-DSA for digital signatures in 2024. Hoskinson said the standards' security parameters account for known attacks.
Hoskinson also rejected Buterin's illustrative suggestion that multiplying key sizes by ten might protect public-key encryption against AI-driven mathematical advances. Hoskinson called that multiplier "numerology" and argued that security parameters must be adjusted according to measurable improvements in attack algorithms. A change in attack efficiency might justify moderately larger parameters. A fundamental mathematical breakthrough could require replacing an algorithm altogether.
Hoskinson challenged the assumption that hash-based cryptography offers greater protection against unforeseen mathematical discoveries. Hoskinson cited historical weaknesses in MD5 and SHA-1 as evidence that hash functions can contain exploitable structures. However, those failures do not establish vulnerabilities in modern constructions such as SHA-256. Hoskinson also criticized Poseidon and Poseidon2, hash functions designed for efficient use in zero-knowledge proofs and relevant to Ethereum's longer-term cryptographic research. The Ethereum Foundation has funded research into Poseidon's resistance to algebraic attacks, including investigations using Gröbner bases and other cryptanalytic methods. Hoskinson argued that these designs also present potential targets for AI-assisted mathematical discoveries and questioned why lattice-based systems should face greater skepticism.
Hash-based signatures can provide quantum-resistant transaction authorization. Lattice techniques also support key encapsulation for encryption and other advanced cryptographic constructions. Abandoning lattice research could therefore limit developers' options for privacy systems, secure communications and other applications requiring those capabilities.