RabbitMQ: CORS * reflects Origin with Allow-Credentials

{
  "id": "70f86a5a5b93410bdc896236105774fc5148e264b1bb32e942dfb09be9ddcd32",
  "url": "https://osv.dev/vulnerability/BIT-rabbitmq-2026-66070",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "RabbitMQ: CORS * reflects Origin with Allow-Credentials",
    "summary": "RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.17, 4.0.22, 4.1.13, and 4.2.6, match_origin/1 returned the bare reflected Origin and allowed credentials even when the wildcard \"\" was configured, so the response echoed the attacker's origin together with Access-Control-Allow-Credentials. The affected code is rabbit_mgmt_cors.erl. When the management plugin is configured with a wildcard CORS origin (cors_allow_origins = \"\"), the handler reflects the request Origin back in Access-Control-Allow-Origin and also sends Access-Control-Allow-Credentials: true. A malicious web page that a signed-in administrator visits can then use that administrator's cached HTTP Basic credentials to issue authenticated, state-changing requests to the management API. Preconditions include The management plugin is configured with the wildcard cors_allow_origins = \"*\", which is an explicit operator misconfiguration A target administrator has a cached HTTP Basic-auth session in the browser. This issue is fixed in versions 3.13.17, 4.0.22, 4.1.13, and 4.2.6.",
    "evidence": "osv:BIT-rabbitmq-2026-66070",
    "products": [
      {
        "name": {
          "value": "rabbitmq",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "3.13.17",
            "evidence": "/affected/0/ranges"
          },
          {
            "value": "4.0.22",
            "evidence": "/affected/0/ranges"
          },
          {
            "value": "4.1.13",
            "evidence": "/affected/0/ranges"
          },
          {
            "value": "4.2.6",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "BIT-rabbitmq-2026-66070",
      "aliases": [
        "BIT-rabbitmq-2026-66070",
        "CVE-2026-66070",
        "GHSA-p3hp-v9wh-ghm7"
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "3.13.0"
                },
                {
                  "fixed": "3.13.17"
                },
                {
                  "introduced": "4.0.0"
                },
                {
                  "fixed": "4.0.22"
                },
                {
                  "introduced": "4.1.0"
                },
                {
                  "fixed": "4.1.13"
                },
                {
                  "introduced": "4.2.0"
                },
                {
                  "fixed": "4.2.6"
                }
              ]
            }
          ],
          "package": {
            "name": "rabbitmq",
            "purl": "pkg:bitnami/rabbitmq",
            "ecosystem": "Bitnami"
          },
          "severity": [
            {
              "type": "CVSS_V4",
              "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"
            }
          ],
          "database_specific": {
            "source": "https://github.com/bitnami/vulndb/tree/main/data/rabbitmq/BIT-rabbitmq-2026-66070.json"
          }
        }
      ],
      "modified": "2026-10-20T10:30:05.384987243Z",
      "provider": "osv",
      "references": [
        "https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6",
        "https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-p3hp-v9wh-ghm7",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-66070"
      ],
      "provider_metadata": {
        "cpes": [
          "cpe:2.3:a:vmware:rabbitmq:*:*:*:*:*:*:*:*"
        ],
        "severity": "High"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-66070",
        "evidence": "/aliases"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/database_specific/severity"
  },
  "source_id": "core-osv",
  "document_id": 379077,
  "published_at": "2026-10-01T09:32:45.642+00:00"
}