Auth bypass in Broadcom Rabbitmq Server
CVE-2026-57221
RabbitMQ is a messaging and streaming broker. Prior to 3.13.15, 4.0.20, 4.1.11, and 4.2.6, RabbitMQ does not perform authorization checks on passive queue.declare and exchange.declare AMQP 0-9-1 operations, allowing any authenticated user who can connect to a virtual host to enumerate queue and exchange names and read queue message and consumer counts. This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.0 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.004 (33.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 33rd percentile — 33.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.004 · change: -0.001
Affected products
- Broadcom Rabbitmq Server
- Rabbitmq Rabbitmq-Server — versions >= 4.2.0, < 4.2.6, >= 4.1.0, < 4.1.11, >= 4.0.0, < 4.0.21
Weakness classification (CWE)
References
- github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-9q2j-2hq8-22r2 (Exploit, Vendor Advisory)
- github.com/rabbitmq/rabbitmq-server/pull/16085 (Patch, Issue Tracking)
- github.com/rabbitmq/rabbitmq-server/pull/16090 (Patch, Issue Tracking)
- github.com/rabbitmq/rabbitmq-server/commit/709a14e49e06c138a8cd672c9809ca34a276… (Patch)
- github.com/rabbitmq/rabbitmq-server/commit/dc3d1aa4f5c3331a425ee599b45be9423a2e… (Patch)
- github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6 (Release Notes)
Frequently asked questions
- What is CVE-2026-57221?
- CVE-2026-57221 is a medium-severity vulnerability in Broadcom Rabbitmq Server, classified under Missing Authorization. CVSS score: 5.0/10. Published 2026-07-10.
- How severe is CVE-2026-57221?
- Medium severity. CVSS v3 base score is 5.0 out of 10.