{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "1.2.1"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4594ab4c779d08be1f4419803a8249188f35ed5f"
            }
          ],
          "repo": "https://github.com/sigstore/sigstore-go",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-wqqc-jjcq-vfxm"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-324"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54787.json"
  },
  "details": "sigstore-go is a Go library for Sigstore signing and verification. Prior to 1.2.1, sigstore-go does not check a bundle signing timestamp against the validity window of an ExpiringKey wrapping a self-managed long-lived signing key without a certificate, which can allow an attacker holding expired key material to sign accepted bundles. This issue is fixed in version 1.2.1.",
  "id": "CVE-2026-54787",
  "modified": "2026-08-02T03:32:14.721068271Z",
  "published": "2026-07-31T21:58:14.156Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/sigstore/sigstore-go/releases/tag/v1.2.1"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54787.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/sigstore/sigstore-go/security/advisories/GHSA-wqqc-jjcq-vfxm"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-54787"
    },
    {
      "type": "FIX",
      "url": "https://github.com/sigstore/sigstore-go/commit/4594ab4c779d08be1f4419803a8249188f35ed5f"
    },
    {
      "type": "FIX",
      "url": "https://github.com/sigstore/sigstore-go/pull/642"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "sigstore-go fails to check signature timestamps against a signing key's validity period"
}