# CVE-2026-67228: RabbitMQ atom table exhaustion denial of service in runtime-parameters

Source: https://junglewise.ai/threats/cve-2026-67228-rabbitmq-is-a-messaging-and-streaming-broker-prior-to-versions-4  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-23. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-67228 · Severity: info · Published 2026-09-23

RabbitMQ is a messaging broker that routes and stores messages between applications. A privileged user (policymaker) can trigger a denial of service by sending roughly one million requests with varying component values, which exhausts the Erlang atom table and crashes the message broker. This requires administrative privileges and repeated requests, but can take down the entire system.

Technologies: [VMware RabbitMQ](https://junglewise.ai/threats/technologies/vmware-rabbitmq). Vendors: [VMware](https://junglewise.ai/threats/vendors/vmware).

## Quick answers

**Is CVE-2026-67228 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-67228 being exploited in the wild.

**How severe is CVE-2026-67228?** Informational severity, published 23 September 2026.

**Which products and versions are affected?** VMware RabbitMQ prior to 4.2.7 and 4.3.1.

**Is there a fix for CVE-2026-67228?** A patch was published on 2026-05: Fixed in versions 4.2.7 and 4.3.1 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-67228 attacked?** It is attacked over the network, in a hosted service.

**Am I affected by CVE-2026-67228?** Check whether you run VMware RabbitMQ at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability exists in the lookup_component/1 function in rabbit_runtime_parameters.erl, which coerces user-supplied URL component segments to atoms using rabbit_data_coercion:to_atom/1. Unlike the safer binary_to_existing_atom helper that already exists in the codebase, this call creates new atoms for unseen values without bounds checking. Since Erlang atoms are not garbage-collected and the atom table is bounded, repeated distinct values can exhaust the table, crashing the node.

## Affected products

- VMware RabbitMQ prior to 4.2.7 and 4.3.1

## Timeline

- 2026-09-23: disclosed
- 2026-05: patched: Fixed in versions 4.2.7 and 4.3.1

## References

- [https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.7](https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.7)
- [https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.1](https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.1)

## Related threats

- [RabbitMQ MQTT 5 parser invalid property denial of service](https://junglewise.ai/threats/cve-2026-67418-rabbitmq-is-a-messaging-and-streaming-broker-from-3-13-0-until-3)
- [RabbitMQ AMQP 1.0 parser descriptor validation bypass](https://junglewise.ai/threats/cve-2026-67416-rabbitmq-is-a-messaging-and-streaming-broker-from-4-0-0-until-4-0)
- [RabbitMQ AMQP 1.0 parser memory exhaustion](https://junglewise.ai/threats/cve-2026-67414-rabbitmq-is-a-messaging-and-streaming-broker-from-4-0-0-until-4-0)
- [RabbitMQ Management XSS via queue name in OAuth UI](https://junglewise.ai/threats/cve-2026-67421-rabbitmq-is-a-messaging-and-streaming-broker-from-3-13-0-until-3)
- [RabbitMQ JMS topic exchange denial of service via regex wildcard expansion](https://junglewise.ai/threats/cve-2026-67413-rabbitmq-is-a-messaging-and-streaming-broker-from-4-0-0-until-4-0)