---
id: CVE-2026-66078
title: RabbitMQ is a messaging and streaming broker
summary: >-
  RabbitMQ is a messaging and streaming broker. From 3.13.0 until 3.13.15 and
  4.0.20 and 4.1.11 and 4.2.6, protected tag bypass via bulk-delete. dELETE
  /api/users/:name refuses to delete users tagged protected
  (rabbitmgmtwmuser:deleteresou…
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H'
cwe:
  - CWE-862
  - CWE-420
vendor: broadcom
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:
  - rabbitmq_server 4.2.6
published: '2026-09-25'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T20:07:28.857'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-66078'
references:
  - url: >-
      https://github.com/rabbitmq/rabbitmq-server/commit/e5b890a64b42ec1f79a8e9d735512150cf77479c
    label: security-advisories@github.com
  - 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-j9m2-hw6x-rqr9
    label: security-advisories@github.com
  - url: >-
      https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-j9m2-hw6x-rqr9
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-66078.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-66078'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2541499'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-66078'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-66078'
  - url: 'https://access.redhat.com/errata/RHSA-2026:67552'
tags:
  - nvd
  - cve.org
  - exploit-available
  - csaf
  - vex
  - red-hat
  - score-dispute
epss: 0.0043
epssPercentile: 0.37089
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-09-29T19:23:41.607515Z'
scores:
  nvd: 5.5
  cna: 2.1
  vendor: 2.7
ingestedAt: '2026-09-25T17:13:14.028Z'
---

## Overview

RabbitMQ is a messaging and streaming broker. From 3.13.0 until 3.13.15 and 4.0.20 and 4.1.11 and 4.2.6, protected tag bypass via bulk-delete. dELETE /api/users/:name refuses to delete users tagged protected (rabbitmgmtwmuser:deleteresource/2 checks isprotecteduser). POST /api/users/bulk-delete iterates the supplied username list and calls rabbitauthbackendinternal:deleteuser/2 directly , that function has no protected-tag check , so the guard is silently An administrator can delete protected-tagged service accounts via the bulk endpoint, bypassing a safeguard the test suite confirms is rabbitmqmanagement enabled Attacker has the administrator tag A protected-tagged user. This issue is fixed in versions 3.13.15 and 4.0.20 and 4.1.11 and 4.2.6.

## 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`

## Remediation

Upgrade past the affected range:

- `rabbitmq_server 4.2.6`

## 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** · Low · 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 2026-10-17 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-66078.json)