Auth bypass in Broadcom Rabbitmq Server
CVE-2026-67412
RabbitMQ is a messaging and streaming broker. From 3.13.0 until 4.3.3, 4.2.9 , 4.1.14, 4.0.24, and 3.13.18, Federation upstream in RabbitMQ skips vhost authorization allowing cross-vhost message access. what the bug lets you do. A policymaker on one vhost reads and drains messages out of another vhost it has no permission on. With the default ack-mode the source messages are consumed (deleted), not copied. Why that should not 1. Federation validates the upstream URI without any vhost-access Cross-vhost message read/drain from a per-vhost policymaker, breaking vhost tenancy This issue is fixed in versions 4.3.3, 4.2.9 , 4.1.14, 4.0.24, and 3.13.18.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (18.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 18th percentile — 18.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Broadcom Rabbitmq Server
- Rabbitmq Rabbitmq-Server — versions >= 3.13.0, < 3.13.18, >= 4.0.0, < 4.0.24, >= 4.1.0, < 4.1.14
Weakness classification (CWE)
References
- https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-42pc-678q-v8qj (Exploit, Vendor Advisory)
- https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.9 (Release Notes)
- https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.3 (Release Notes)
Frequently asked questions
- What is CVE-2026-67412?
- CVE-2026-67412 is a high-severity vulnerability in Broadcom Rabbitmq Server, classified under Missing Authorization. CVSS score: 7.1/10. Published 2026-09-25.
- How severe is CVE-2026-67412?
- High severity. CVSS v3 base score is 7.1 out of 10.