---
id: CVE-2026-67219
title: RabbitMQ is a messaging and streaming broker
summary: >-
  RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15,
  4.0.20, 4.1.11, 4.2.6, and 4.3.0, add_binding/3 parses the routing key as an
  integer weight N and computes ring positions with lists:seq(NextN0, NextN0 + N
  - 1). va…
severity: medium
cvss: 6
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'
cwe:
  - CWE-770
  - CWE-606
vendor: rabbitmq
product: rabbitmq-server
affected:
  - 'rabbitmq-server >= 3.13.0, < 3.13.15'
  - 'rabbitmq-server >= 4.0.0, < 4.0.20'
  - 'rabbitmq-server >= 4.1.0, < 4.1.11'
  - 'rabbitmq-server >= 4.2.0, < 4.2.6'
patched:
  - hardened_images
published: '2026-09-23'
updated: '2026-09-24'
sourceUpdated: '2026-09-24T15:17:29.547'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-67219'
references:
  - url: 'https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6'
    label: security-advisories@github.com
  - url: 'https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.0'
    label: security-advisories@github.com
  - url: >-
      https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-m8pg-4x2h-jvgr
    label: security-advisories@github.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-67219.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-67219'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2539785'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-67219'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-67219'
  - url: 'https://access.redhat.com/errata/RHSA-2026:67552'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-24T14:19:46.502402Z'
cvssSource: cna
scores:
  cna: 6
  vendor: 6.5
ingestedAt: '2026-09-23T21:33:13.529Z'
epss: 0.00259
epssPercentile: 0.15672
---

## Overview

RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0, add_binding/3 parses the routing key as an integer weight N and computes ring positions with lists:seq(NextN0, NextN0 + N - 1). validate_binding/2 only checks N >= 1 , no upper bound. The resulting list is stored in the exchange's Khepri record, replicated cluster-wide, and reloaded on restart. A user with write permission on a consistent-hash exchange and read on a queue can create a binding whose routing key (the hash-ring weight) is an arbitrarily large integer. The broker allocates a list of that many integers via lists:seq/2 and persists it to Khepri across all cluster nodes , a single binding with weight 100000000 allocates ~800 MB on every node and survives restarts. Preconditions include rabbitmq_consistent_hash_exchange plugin enabled write permission on a consistent-hash exchange + read on a queue (standard binding perms). This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0.

## Remediation

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

## 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 · no fix planned: Red Hat Hardened Images · updated 2026-09-24 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-67219.json)