{
  "type": "failure-mode",
  "name": "Non-deterministic or malleable witness generation",
  "slug": "non-deterministic-or-malleable-witness-generation",
  "section": {
    "id": "audit",
    "number": "03",
    "title": "Auditing a ZK protocol",
    "url": "https://zkpick.com/audit/"
  },
  "url": "https://zkpick.com/audit/failure-modes/non-deterministic-or-malleable-witness-generation/",
  "markdown": "https://zkpick.com/md/audit/failure-modes/non-deterministic-or-malleable-witness-generation.md",
  "detail": "More than one witness satisfies the constraints for the same logical input, allowing an attacker to produce a distinct valid proof for the same action — which breaks any logic that assumed proofs or their derived values are unique.",
  "mitigation": "Constrain witness generation to a canonical form. Where uniqueness matters downstream, enforce it in the circuit rather than relying on the honest prover implementation.",
  "relatedOptions": [],
  "updated": "2026-09-12",
  "version": "1.3",
  "canonical": "https://zkpick.com/audit/failure-modes/non-deterministic-or-malleable-witness-generation/",
  "license": "https://creativecommons.org/licenses/by/4.0/",
  "authors": [
    "MarketComp"
  ]
}