{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "4.3.0"
              },
              {
                "fixed": "4.3.5"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "1929eeadf9b2bac12c5434fb56884ef27370580e"
            },
            {
              "fixed": "ff595eaaa6d4f580f72fa04801ffd35f48c46027"
            },
            {
              "fixed": "0dde27bfdd1984ff7e157226fd97656854a7f359"
            }
          ],
          "repo": "https://github.com/rabbitmq/rabbitmq-server",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-6256-27fm-4rgr"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-862"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/67xxx/CVE-2026-67421.json",
    "unresolved_ranges": [
      {
        "extracted_events": [
          {
            "introduced": "3.13.0"
          },
          {
            "fixed": "3.13.19"
          },
          {
            "introduced": "4.0.0"
          },
          {
            "fixed": "4.0.24"
          },
          {
            "introduced": "4.1.0"
          },
          {
            "fixed": "4.1.15"
          },
          {
            "introduced": "4.2.0"
          },
          {
            "fixed": "4.2.10"
          }
        ],
        "source": "AFFECTED_FIELD"
      }
    ]
  },
  "details": "RabbitMQ is a messaging and streaming broker. From 3.13.0 until 3.13.19, 4.0.24, 4.1.15, 4.2.10, and 4.3.5, RabbitMQ Management rendered an AMQP authorization-error reason containing an attacker-controlled queue name as HTML when the OAuth management UI was enabled. Exploitation requires an attacker with queue configure permission, a management administrator who can see but cannot read that queue, and the administrator clicking Get Message(s). A queue name containing a base element can then retarget the automatic relative refresh because the Content Security Policy omits base-uri and connect-src, and an attacker endpoint that permits the management origin through CORS can receive the victim's Authorization header. This issue is fixed in versions 3.13.19, 4.0.24, 4.1.15, 4.2.10, and 4.3.5.",
  "id": "CVE-2026-67421",
  "modified": "2026-09-27T03:30:47.971863430Z",
  "published": "2026-09-25T16:39:02.323Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.5"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/67xxx/CVE-2026-67421.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-6256-27fm-4rgr"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-67421"
    },
    {
      "type": "FIX",
      "url": "https://github.com/rabbitmq/rabbitmq-server/commit/ff595eaaa6d4f580f72fa04801ffd35f48c46027"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:L/VI:L/VA:N/SC:H/SI:L/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "RabbitMQ: Stored HTML Injection in RabbitMQ Management OAuth Error Handling"
}