---
id: CVE-2026-67419
title: RabbitMQ is a messaging and streaming broker
summary: >-
  RabbitMQ is a messaging and streaming broker. Prior to 4.3.5, an authenticated
  user who can bind a queue to a topic exchange and publish to it can use
  consecutive # segments in a binding key to make both topic matchers revisit
  the same t…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-407
  - CWE-1333
vendor: broadcom
product: rabbitmq_server
affected:
  - 'rabbitmq_server >= 4.3.0, < 4.3.5'
patched:
  - rabbitmq_server 4.3.5
published: '2026-09-25'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T15:46:33.137'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-67419'
references:
  - url: >-
      https://github.com/rabbitmq/rabbitmq-server/commit/c5ed7c4e97e02be688730803604cc7a88dbe4864
    label: security-advisories@github.com
  - url: 'https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.5'
    label: security-advisories@github.com
  - url: >-
      https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-h964-v5mf-22cq
    label: security-advisories@github.com
  - url: >-
      https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-h964-v5mf-22cq
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-67419.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-67419'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2541534'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-67419'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-67419'
  - url: 'https://access.redhat.com/errata/RHSA-2026:67552'
tags:
  - nvd
  - cve.org
  - exploit-available
  - csaf
  - vex
  - red-hat
epss: 0.00373
epssPercentile: 0.31046
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-25T17:01:28.563642Z'
scores:
  nvd: 6.5
  cna: 7.1
  vendor: 6.5
ingestedAt: '2026-09-25T17:13:14.018Z'
---

## Overview

RabbitMQ is a messaging and streaming broker. Prior to 4.3.5, an authenticated user who can bind a queue to a topic exchange and publish to it can use consecutive # segments in a binding key to make both topic matchers revisit the same trie-node and routing-key-suffix states without memoization. The matcher materializes duplicate destinations before deduplication, causing combinatorial CPU work and memory pressure that can disrupt routing for all tenants. This vulnerability is fixed in 4.3.5.

## Affected

- `rabbitmq_server >= 4.3.0, < 4.3.5`

## Remediation

Upgrade past the affected range:

- `rabbitmq_server 4.3.5`

## Vendor advisories

- **RHSA-2026:67552** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-09-15 · [advisory](https://access.redhat.com/errata/RHSA-2026:67552)
- **Red Hat VEX** · Moderate · affected: Red Hat Hardened Images, Red Hat OpenStack Platform 13 (Queens), Red Hat OpenStack Platform 16.2, Red Hat OpenStack Platform 17.1, Red Hat OpenStack Platform 18.0 · no fix planned: Red Hat OpenStack Platform 13 (Queens), Red Hat OpenStack Platform 16.2, Red Hat OpenStack Platform 17.1, Red Hat Hardened Images, … · updated 2026-10-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-67419.json)