Auth bypass in Broadcom Rabbitmq Server
CVE-2026-57216
RabbitMQ is a messaging and streaming broker. Prior to 3.13.15, 4.0.20, 4.1.11, and 4.2.6, AMQP 0-9-1, AMQP 1.0, and Stream Protocol authentication can allow a loopback-restricted user such as guest to connect remotely when traffic is accepted through a trusted PROXY-protocol path and the backend listener is loopback-bound because the loopback check uses the listener-side socket address instead of the real client source. This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.005 (41.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 41.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.009 · newest: 0.005 · change: -0.004
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-36m6-588r-vqcw (Exploit, Vendor Advisory)
- github.com/rabbitmq/rabbitmq-server/pull/15936 (Patch, Issue Tracking)
- github.com/rabbitmq/rabbitmq-server/pull/15940 (Patch, Issue Tracking)
- github.com/rabbitmq/rabbitmq-server/commit/7273c9eb6920abcde17b892dbe97ccaf906e… (Patch)
- github.com/rabbitmq/rabbitmq-server/commit/9f8c39fcf0acbc43080ee7017a62a0283211… (Patch)
- github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6 (Release Notes)
Frequently asked questions
- What is CVE-2026-57216?
- CVE-2026-57216 is a medium-severity vulnerability in Broadcom Rabbitmq Server, classified under Improper Authentication. CVSS score: 6.8/10. Published 2026-07-10.
- How severe is CVE-2026-57216?
- Medium severity. CVSS v3 base score is 6.8 out of 10.