# CVE-2026-67239: RabbitMQ: Stored XSS via TLS peer-certificate DN in stream-management UI

CVE-2026-67239 is fixed in rabbitmq-server on 1 platform, first by rabbitmq-server 4.0.5-10ubuntu5.2, released September 25, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-67239
- Priority: Routine
- CVSS: 5.4 (Moderate)
- EPSS: 0.0015
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 25, 2026
- Weakness: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-67239

## Description

RabbitMQ is a messaging and streaming broker. From 3.13.0 until 3.13.18 and 4.0.23 and 4.1.14 and 4.2.9 and 4.3.3, Stored XSS via TLS peer-certificate DN in stream-management UI (sibling of V-11). lines 102/106/110 render peercertsubject / peercertissuer with raw <%= %> and no fmtstring(). RFC4514 backslash-escaping of </> is HTML-inert and bypassable (<img ... //>). Requires non-default config: a stream TLS listener with verifypeer and an attacker-obtainable trusted cert with a malicious Same as the connection.ejs finding, against operators viewing the stream-connection detail rabbitmqstream + rabbitmqstreammanagement enabled with a TLS listener using verifypeer Attacker can obtain a certificate signed by a CA the listener trusts, with attacker-chosen DN An operator views the. This issue is fixed in versions 3.13.18 and 4.0.23 and 4.1.14 and 4.2.9 and 4.3.3.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | rabbitmq-server Debian 14 | 4.3.6-1 | [DEBIAN-CVE-2026-67239](https://patchblox.com/security/data/fix/linux/debian-cve-2026-67239.md) | Oct 10, 2026 |
| Linux | rabbitmq-server Ubuntu 18.04.6 LTS (bionic) | 3.6.10-1ubuntu0.5+esm1 | [rabbitmq-server 3.6.10-1ubuntu0.5+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-rabbitmq-server-3.6.10-1ubuntu0.5-esm1.md) | Oct 19, 2026 |
| Linux | rabbitmq-server Ubuntu 20.04 LTS (focal) | 3.8.3-0ubuntu0.3+esm2 | [rabbitmq-server 3.8.3-0ubuntu0.3+esm2](https://patchblox.com/security/data/fix/linux/ubuntu-focal-rabbitmq-server-3.8.3-0ubuntu0.3-esm2.md) | Oct 19, 2026 |
| Linux | rabbitmq-server Ubuntu 22.04.1 LTS (jammy) | 3.9.27-0ubuntu0.6 | [rabbitmq-server 3.9.27-0ubuntu0.6](https://patchblox.com/security/data/fix/linux/ubuntu-jammy-rabbitmq-server-3.9.27-0ubuntu0.6.md) | Oct 19, 2026 |
| Linux | rabbitmq-server Ubuntu 24.04.5 LTS (noble) | 3.12.1-1ubuntu1.7 | [rabbitmq-server 3.12.1-1ubuntu1.7](https://patchblox.com/security/data/fix/linux/ubuntu-noble-rabbitmq-server-3.12.1-1ubuntu1.7.md) | Oct 19, 2026 |
| Linux | rabbitmq-server Ubuntu 26.04.1 LTS (resolute) | 4.0.5-10ubuntu5.2 | [rabbitmq-server 4.0.5-10ubuntu5.2](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-rabbitmq-server-4.0.5-10ubuntu5.2.md) | Sep 25, 2026 |

---

Data as of 2026-11-08T00:53:09Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.