{"id":"CVE-2026-67411","aliases":["BIT-rabbitmq-2026-67411","GHSA-4r6f-9cpw-f6g6"],"url":"https://o3.security/vulnerability/CVE-2026-67411","summary":"RabbitMQ: Web MQTT with PROXY Protocol enabled: a loopback-only user permission bypass","details":"RabbitMQ is a messaging and streaming broker. From 3.13.0 until 3.13.18, 4.0.23, 4.1.14, 4.2.9, and 4.3.3, native MQTT and MQTT over WebSocket behind a trusted PROXY Protocol frontend could lose the proxy-derived client address before the MQTT authentication path checked loopback_users, causing the frontend-to-broker address to be treated as loopback. An attacker who can reach the trusted frontend and has valid credentials for a loopback-restricted account can therefore bypass the source-address restriction; the issue does not bypass password authentication. This issue is fixed in versions 3.13.18, 4.0.23, 4.1.14, 4.2.9, and 4.3.3.","published":"2026-09-25T16:26:33.880Z","modified":"2026-10-01T10:10:49.437773075Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Bitnami","name":"rabbitmq","fixedVersion":"3.13.18"}],"fix":{"url":"https://github.com/rabbitmq/rabbitmq-server/commit/a7528314840c4f8dc9904684f9f97ffa7aac6349","label":"rabbitmq/rabbitmq-server@a752831"},"references":[{"type":"WEB","url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.9"},{"type":"WEB","url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.3"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/67xxx/CVE-2026-67411.json"},{"type":"ADVISORY","url":"https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-4r6f-9cpw-f6g6"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-67411"},{"type":"FIX","url":"https://github.com/rabbitmq/rabbitmq-server/commit/a7528314840c4f8dc9904684f9f97ffa7aac6349"},{"type":"FIX","url":"https://github.com/rabbitmq/rabbitmq-server/commit/edbead0eabbd65925d0dc914a22d6a29e155e646"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-01T10:10:49.437773075Z"}}