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

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-25 · updated 2026-10-16
Weakness: CWE-79

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.

Affected products

rabbitmq-server: from 3.13.0 before 3.13.18; from 4.0.0 before 4.0.23; from 4.1.0 before 4.1.14; from 4.2.0 before 4.2.9; from 4.3.0 before 4.3.3 — fixed in 3.13.18, 4.0.23, 4.1.14, 4.2.9, 4.3.3

How to fix

Upgrade to a fixed version: rabbitmq-server 3.13.18, 4.0.23, 4.1.14, 4.2.9. Check the vendor advisory for mitigations.

References

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