---
id: CVE-2026-66070
title: RabbitMQ is a messaging and streaming broker
summary: >-
  RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.17,
  4.0.22, 4.1.13, and 4.2.6, match_origin/1 returned the bare reflected Origin
  and allowed credentials even when the wildcard "" was configured, so the
  response echoe…
severity: high
cvss: 7.6
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N'
cwe:
  - CWE-942
vendor: rabbitmq
product: rabbitmq-server
affected:
  - 'rabbitmq-server >= 3.13.0, < 3.13.17'
  - 'rabbitmq-server >= 4.0.0, < 4.0.22'
  - 'rabbitmq-server >= 4.1.0, < 4.1.13'
  - 'rabbitmq-server >= 4.2.0, < 4.2.6'
published: '2026-09-23'
updated: '2026-09-24'
sourceUpdated: '2026-09-24T15:17:28.250'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-66070'
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/security/advisories/GHSA-p3hp-v9wh-ghm7
    label: security-advisories@github.com
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-24T14:16:50.638390Z'
cvssSource: cna
ingestedAt: '2026-09-23T20:32:10.747Z'
---

## Overview

RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.17, 4.0.22, 4.1.13, and 4.2.6, match_origin/1 returned the bare reflected Origin and allowed credentials even when the wildcard "" was configured, so the response echoed the attacker's origin together with Access-Control-Allow-Credentials. The affected code is rabbit_mgmt_cors.erl. When the management plugin is configured with a wildcard CORS origin (cors_allow_origins = ""), the handler reflects the request Origin back in Access-Control-Allow-Origin and also sends Access-Control-Allow-Credentials: true. A malicious web page that a signed-in administrator visits can then use that administrator's cached HTTP Basic credentials to issue authenticated, state-changing requests to the management API. Preconditions include The management plugin is configured with the wildcard cors_allow_origins = "*", which is an explicit operator misconfiguration A target administrator has a cached HTTP Basic-auth session in the browser. This issue is fixed in versions 3.13.17, 4.0.22, 4.1.13, and 4.2.6.

## Remediation

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