---
id: CVE-2026-67234
title: RabbitMQ is a messaging and streaming broker
summary: >-
  RabbitMQ is a messaging and streaming broker. From 4.2.0 until 4.2.8 and
  4.3.2, get_auth_mechanism/1 used term_to_binary/1 on the strict_auth_mechanism
  or preferred_auth_mechanism atom when clearing the corresponding cookie,
  producing a …
severity: low
cvss: 2.3
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N'
cwe:
  - CWE-20
vendor: rabbitmq
product: rabbitmq-server
affected:
  - 'rabbitmq-server >= 4.2.0, < 4.2.8'
  - 'rabbitmq-server >= 4.3.0, < 4.3.2'
published: '2026-09-25'
updated: '2026-09-25'
sourceUpdated: '2026-09-25T20:17:38.987'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-67234'
references:
  - url: >-
      https://github.com/rabbitmq/rabbitmq-server/commit/149cb59d618cefa83c6deb02dbbb1e8a7a2bc968
    label: security-advisories@github.com
  - url: >-
      https://github.com/rabbitmq/rabbitmq-server/commit/baac0aaf170efeb4f124ee36b8417274fa8dcc1a
    label: security-advisories@github.com
  - url: 'https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.8'
    label: security-advisories@github.com
  - url: 'https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.2'
    label: security-advisories@github.com
  - url: >-
      https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-q286-p3m9-j69f
    label: security-advisories@github.com
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-25T19:53:50.305307Z'
cvssSource: cna
ingestedAt: '2026-09-25T17:13:14.030Z'
---

## Overview

RabbitMQ is a messaging and streaming broker. From 4.2.0 until 4.2.8 and 4.3.2, get_auth_mechanism/1 used term_to_binary/1 on the strict_auth_mechanism or preferred_auth_mechanism atom when clearing the corresponding cookie, producing a non-ASCII cookie name that violates RFC 6265 and can prevent the browser from deleting the preference. The issue is not directly exploitable for code execution or data exfiltration; its security relevance is limited to stale authentication-mechanism preferences persisting across logout and login cycles. This issue is fixed in versions 4.2.8 and 4.3.2.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.