{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "2.11.16"
              },
              {
                "introduced": "2.12.0-preview.1"
              },
              {
                "fixed": "2.12.6"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "introduced": "ef5569d9005b1c12f4ef84a01932fcdd1cea8faa"
            },
            {
              "fixed": "8a6b7cd9ac62105dcc9db70e589932d3b2548b36"
            },
            {
              "fixed": "0e0639058e0d2d8fce0cc34941f9897da152ab32"
            },
            {
              "fixed": "7b81dd455ea95960090a84858c7662827948d1b6"
            },
            {
              "fixed": "8b8e1ad4ceed32321e00d4fc6e76be05bc13bca6"
            },
            {
              "fixed": "b86147e81710a52b72a7f7275f91d69f723f5cb3"
            },
            {
              "fixed": "b4ce0f990e42bc6f24df0c40eafbc4c8a2ac5b6c"
            },
            {
              "fixed": "0cbd01caf8f29011c26273ff7662addd3830396a"
            }
          ],
          "repo": "https://github.com/nats-io/nats-server",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-38x3-76xf-cq45"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-287"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/58xxx/CVE-2026-58253.json"
  },
  "details": "NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.0, 2.12.7, and 2.11.16, when no_auth_user was configured, a parser fast path intended for ordinary client connections could also apply to route or leafnode listeners, allowing an unauthenticated peer to bypass inter-server CONNECT authentication and operate with the privileges associated with that connection type. This issue is fixed in versions 2.14.0, 2.12.7, and 2.11.16.",
  "id": "CVE-2026-58253",
  "modified": "2026-07-11T03:54:02.176153765Z",
  "published": "2026-07-08T19:43:13.776Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/nats-io/nats-server/releases/tag/v2.11.16"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nats-io/nats-server/releases/tag/v2.12.7"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nats-io/nats-server/releases/tag/v2.14.0"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/58xxx/CVE-2026-58253.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/nats-io/nats-server/security/advisories/GHSA-38x3-76xf-cq45"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-58253"
    },
    {
      "type": "FIX",
      "url": "https://github.com/nats-io/nats-server/commit/7b81dd455ea95960090a84858c7662827948d1b6"
    },
    {
      "type": "FIX",
      "url": "https://github.com/nats-io/nats-server/commit/8b8e1ad4ceed32321e00d4fc6e76be05bc13bca6"
    },
    {
      "type": "FIX",
      "url": "https://github.com/nats-io/nats-server/commit/b86147e81710a52b72a7f7275f91d69f723f5cb3"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "NATS Server: Route API Auth Bypass"
}