What’s Vulnerable › Vulnerabilities

CVE-2026-57216: RabbitMQ: AMQP 1.0, AMQP 0-9-1, Stream Protocol loopback enforcement can lead to remote guest sessions due to listener-address loopback checks

• Severity: critical (CVSS 10.0 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-07-10 · updated 2026-10-25
• Weakness: CWE-287

Description

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.

Affected products

• rabbitmq-server: from 3.13.0 before 3.13.15; from 4.0.0 before 4.0.20; from 4.1.0 before 4.1.11; from 4.2.0 before 4.2.6 — fixed in 3.13.15, 4.0.20, 4.1.11, 4.2.6

How to fix

Upgrade to a fixed version: rabbitmq-server 3.13.15, 4.0.20, 4.1.11, 4.2.6. Check the vendor advisory for mitigations.

References

• https://github.com/rabbitmq/rabbitmq-server/commit/7273c9eb6920abcde17b892dbe97ccaf906ead47
• https://github.com/rabbitmq/rabbitmq-server/commit/9f8c39fcf0acbc43080ee7017a62a02832114112
• https://github.com/rabbitmq/rabbitmq-server/pull/15936
• https://github.com/rabbitmq/rabbitmq-server/pull/15940
• https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6
• https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-36m6-588r-vqcw
• https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-36m6-588r-vqcw

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