CVE-2026-66075: RabbitMQ: Monitoring-tag user can restart federation links

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-23 · updated 2026-10-19
Weakness: CWE-862

Description

RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.1, is_authorized/2 for the /federation-links/.../restart route uses is_authorized_monitor (accepts the monitoring tag), while allowed_methods permits DELETE and delete_resource/2 triggers rabbit_federation_link_sup:restart. There is no per-method elevation check and no comment marking it intentional. A read-only monitoring user can restart any federation link , a state-changing operation that disrupts message flow. Preconditions include rabbitmq_federation + rabbitmq_federation_management plugins enabled Attacker has credentials with the monitoring tag. This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.1.

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; from 4.3.0 before 4.3.1 — fixed in 3.13.15, 4.0.20, 4.1.11, 4.2.6, 4.3.1

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

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