Fiber Utils UUIDv4 and UUID Silent Fallback to Predictable Values

{
  "id": "58203c96f3e5caafd5f7cb2c1cc9fb34d8632f0c00068d83b004198c95e70c83",
  "url": "https://osv.dev/vulnerability/CVE-2025-66565",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Fiber Utils UUIDv4 and UUID Silent Fallback to Predictable Values",
    "summary": "Fiber Utils is a collection of common functions created for Fiber. In versions 2.0.0-rc.3 and below, when the system's cryptographic random number generator (crypto/rand) fails, both functions silently fall back to returning predictable UUID values, including the zero UUID \"00000000-0000-0000-0000-000000000000\". The vulnerability occurs through two related but distinct failure paths, both ultimately caused by crypto/rand.Read() failures, compromising the security of all Fiber applications using these functions for security-critical operations. This issue is fixed in version 2.0.0-rc.4.",
    "evidence": "osv:CVE-2025-66565",
    "products": [],
    "severity": "critical",
    "structured": {
      "id": "CVE-2025-66565",
      "aliases": [
        "CVE-2025-66565",
        "GHSA-m98w-cqp3-qcqr",
        "GO-2025-4208"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/gofiber/utils",
              "type": "GIT",
              "events": [
                {
                  "introduced": "b986fcc3965a3570e3b755646a026641af8c2da4"
                },
                {
                  "fixed": "6c6cf047032b9c8dff43d29f990b4b10e9b02d47"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "github.com/gofiber/utils <= 1.2.0"
                      },
                      {
                        "last_affected": "github.com/gofiber/utils <= 1.2.0"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandaloneSingleVersion"
                  },
                  {
                    "range": [
                      {
                        "fixed": "6c6cf047032b9c8dff43d29f990b4b10e9b02d47"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "github.com/gofiber/utils <= 1.2.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-66565.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:51.534899269Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/66xxx/CVE-2025-66565.json",
        "https://github.com/gofiber/utils/security/advisories/GHSA-m98w-cqp3-qcqr",
        "https://nvd.nist.gov/vuln/detail/CVE-2025-66565",
        "https://github.com/gofiber/utils/commit/6c6cf047032b9c8dff43d29f990b4b10e9b02d47"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-252",
          "CWE-331",
          "CWE-338"
        ],
        "cna_assigner": "GitHub_M",
        "unresolved_ranges": [
          {
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "github.com/gofiber/utils/v2 < 2.0.0-rc.4"
                  },
                  {
                    "last_affected": "github.com/gofiber/utils/v2 < 2.0.0-rc.4"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StandaloneSingleVersion"
              }
            ]
          }
        ],
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/66xxx/CVE-2025-66565.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2025-66565",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 520278,
  "published_at": "2025-12-09T01:47:58.43+00:00"
}