{
  "affected": [
    {
      "database_specific": {
        "categories": [
          "crypto-failure"
        ],
        "cvss": null,
        "informational": null
      },
      "ecosystem_specific": {
        "affected_functions": null,
        "affects": {
          "arch": [],
          "functions": [],
          "os": []
        }
      },
      "package": {
        "ecosystem": "crates.io",
        "name": "dcrypt-sign",
        "purl": "pkg:cargo/dcrypt-sign"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.0.0-0"
            },
            {
              "fixed": "2.0.0"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "versions": []
    }
  ],
  "aliases": [
    "GHSA-7j32-2mpw-c784"
  ],
  "database_specific": {
    "license": "CC0-1.0"
  },
  "details": "All published versions of `dcrypt-sign` before 2.0.0 accepted the Edwards\nidentity as an Ed25519 public key. A signature with `R = B` and `S = 1` then\nverified for every message because the challenge term multiplied the identity.\nThe implementation also admitted other noncanonical or small-order inputs.\nConsumers that accepted externally supplied dcrypt Ed25519 keys may therefore\nhave accepted forged authorizations.\n\nVersion 2.0.0 replaces the custom arithmetic with `ed25519-dalek`, uses strict\nverification, and rejects noncanonical, small-order, and non-torsion-free public\nkeys and `R` values, as well as noncanonical `S \u003e= L`. No wrapper around the\naffected verifier is recommended as a complete workaround. Upgrade to 2.0.0 or\nlater, audit registered keys and trust stores, and review historical actions\nauthorized with externally supplied keys.",
  "id": "RUSTSEC-2026-0240",
  "modified": "2026-08-09T12:34:06Z",
  "published": "2026-08-09T12:00:00Z",
  "references": [
    {
      "type": "PACKAGE",
      "url": "https://crates.io/crates/dcrypt-sign"
    },
    {
      "type": "ADVISORY",
      "url": "https://rustsec.org/advisories/RUSTSEC-2026-0240.html"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/ioi-foundation/dcrypt/security/advisories/GHSA-7j32-2mpw-c784"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ioi-foundation/dcrypt/commit/c99cc86f0ee353010cd202cbcd2c310371b0bbb8"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ioi-foundation/dcrypt/releases/tag/v2.0.0"
    }
  ],
  "related": [],
  "severity": [],
  "summary": "Ed25519 identity public keys permit universal signature forgery"
}