{
  "title": "XMSS^MT height-40 keys never report KeyExhausted after last signature",
  "category": "bugs",
  "type": "logic-bug",
  "severity": "low",
  "cvss": null,
  "ecosystem": "rust",
  "project": {
    "owner": "RustCrypto",
    "repo": "signatures",
    "url": "https://github.com/RustCrypto/signatures"
  },
  "affected_versions": [
    "xmss crate (pre-1.0)"
  ],
  "status": "reported",
  "disclosure": {
    "channel": "public-issue",
    "ghsa_id": null,
    "cve_id": null,
    "url": "https://github.com/RustCrypto/signatures/issues/1453",
    "reported_at": "2026-10-05T14:11:31+03:00",
    "published_at": "2026-10-05T14:11:25+03:00"
  },
  "summary": "Public bug report: after signing at the last XMSS^MT height-40 index, KeyExhausted is not raised and further signing returns Ok with an invalid signature. Open issue, no maintainer reply yet.",
  "discovered_at": "2026-10-04T00:00:00+03:00",
  "public": true,
  "credit": "ucsurf",
  "updated_at": "2026-10-07T00:59:34+03:00",
  "pr": null,
  "id": "bugs/rust/RustCrypto__signatures/2026-10-04-xmssmt-h40-keyexhausted-not-detected"
}