CVE-2026-67411
Publication date 29 September 2026
Last updated 29 September 2026
Ubuntu priority
Description
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.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| rabbitmq-server | 26.04 LTS resolute |
Needs evaluation
|
| 24.04 LTS noble |
Needs evaluation
|
|
| 22.04 LTS jammy |
Needs evaluation
|
|
| 20.04 LTS focal |
Needs evaluation
|
|
| 18.04 LTS bionic |
Needs evaluation
|
|
| 16.04 LTS xenial |
Needs evaluation
|
Severity score breakdown
CVSS version: CVSS v4.0
Base score
6.0 · Medium
Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
References
Other references
- https://www.cve.org/CVERecord?id=CVE-2026-67411
- https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-4r6f-9cpw-f6g6
- https://github.com/rabbitmq/rabbitmq-server/commit/a7528314840c4f8dc9904684f9f97ffa7aac6349
- https://github.com/rabbitmq/rabbitmq-server/commit/edbead0eabbd65925d0dc914a22d6a29e155e646
- https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.9
- https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.3