# CVE-2026-66075: RabbitMQ privilege escalation in federation link restart

Source: https://junglewise.ai/threats/cve-2026-66075-rabbitmq-is-a-messaging-and-streaming-broker-prior-to-versions-3  
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-2026-66075 · Severity: info · Published 2026-09-23

RabbitMQ is a messaging broker that handles data routing and queueing. A monitoring user with read-only permissions can restart federation links—a state-changing operation that disrupts message flow between brokers. This allows privilege escalation from read-only access to impacting service availability without proper authorization checks.

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

## Quick answers

**Is CVE-2026-66075 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-66075 being exploited in the wild.

**How severe is CVE-2026-66075?** Informational severity, published 23 September 2026.

**Which products and versions are affected?** RabbitMQ Before 3.13.15, 4.0.20, 4.1.11, 4.2.6, 4.3.1.

**Is there a fix for CVE-2026-66075?** A patch was published on 2026-04-23: RabbitMQ 4.2.6 released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-66075 attacked?** It is attacked over the network, in a hosted service.

**Am I affected by CVE-2026-66075?** Check whether you run 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 /federation-links/.../restart endpoint uses is_authorized_monitor for permission checks (allowing the monitoring tag) but allowed_methods permits DELETE, triggering delete_resource/2 without per-method privilege elevation validation. An attacker with monitoring credentials can invoke the restart operation to disrupt federation links. The vulnerability requires rabbitmq_federation and rabbitmq_federation_management plugins to be enabled.

## Affected products

- RabbitMQ RabbitMQ Before 3.13.15, 4.0.20, 4.1.11, 4.2.6, 4.3.1

## Timeline

- 2026-09-23: disclosed
- 2026-04-23: patched: RabbitMQ 4.2.6 released
- 2026-05-20: patched: RabbitMQ 4.3.1 released

## References

- [https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6](https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6)
- [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 OAuth privilege escalation via stale token tags](https://junglewise.ai/threats/cve-2026-67420-rabbitmq-is-a-messaging-and-streaming-broker-from-3-13-0-until-3)
- [RabbitMQ topic exchange denial of service via duplicate matchers](https://junglewise.ai/threats/cve-2026-67419-rabbitmq-is-a-messaging-and-streaming-broker-prior-to-4-3-5-an)
- [RabbitMQ Shovel denial of service via atom exhaustion](https://junglewise.ai/threats/cve-2026-67415-rabbitmq-is-a-messaging-and-streaming-broker-from-4-2-0-until-4-2)
- [RabbitMQ MQTT loopback user bypass via PROXY Protocol](https://junglewise.ai/threats/cve-2026-67411-rabbitmq-is-a-messaging-and-streaming-broker-from-3-13-0-until-3)
- [RabbitMQ OAuth2 client secret exposure via unauthenticated endpoint](https://junglewise.ai/threats/cve-2026-67410-rabbitmq-is-a-messaging-and-streaming-broker-from-4-2-0-until-4-3)