CVE-2026-67415: RabbitMQ: Shovel Management Atom Exhaustion Allows Persistent Broker-Wide Denial of Service

Severity: medium (CVSS 4.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-09-25 · updated 2026-10-16
Weakness: CWE-400

Description

RabbitMQ is a messaging and streaming broker. From 4.2.0 until 4.2.9 and 4.3.3, the Shovel parameter parser converted attacker-controlled runtime parameter values into non-garbage-collected Erlang atoms before bounding them or checking a fixed allowlist. Exploitation requires network access to the Management HTTP API, valid credentials with both the management and policymaker tags, permission to set Shovel runtime parameters on a vhost, and the rabbitmq_shovel and rabbitmq_shovel_management plugins to be enabled. The attacker can exhaust the node-wide atom table and deny service, and malicious parameters are stored durably and reparsed when workers start, so atom pressure can recur after restart without a live attacker connection. This issue is fixed in versions 4.2.9 and 4.3.3.

Affected products

rabbitmq-server: from 4.2.0 before 4.2.9; from 4.3.0 before 4.3.3 — fixed in 4.2.9, 4.3.3

How to fix

Upgrade to a fixed version: rabbitmq-server 4.2.9, 4.3.3. Check the vendor advisory for mitigations.

References

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