# CVE-2026-66070: RabbitMQ management plugin CORS credential theft with wildcard origin

Source: https://junglewise.ai/threats/cve-2026-66070-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-2026-66070 · Severity: info · Published 2026-09-23

RabbitMQ's management plugin allows administrators to manage the message broker through a web interface. When misconfigured with a wildcard CORS origin setting, the plugin reflects an attacker's origin in responses while also sending credentials, allowing a malicious website to steal an administrator's session and issue state-changing commands to the broker.

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

## Quick answers

**Is CVE-2026-66070 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-66070 being exploited in the wild.

**How severe is CVE-2026-66070?** Informational severity, published 23 September 2026.

**Which products and versions are affected?** RabbitMQ 3.13.0 to 3.13.16, 4.0.0 to 4.0.21, 4.1.0 to 4.1.12, 4.2.0 to 4.2.5.

**Is there a fix for CVE-2026-66070?** A patch was published on 2026-09-23. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-66070 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-66070?** 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 match_origin/1 function in rabbit_mgmt_cors.erl incorrectly reflects the request Origin header in Access-Control-Allow-Origin and sends Access-Control-Allow-Credentials: true when cors_allow_origins is set to "*". An attacker can exploit this via a malicious web page visited by a logged-in administrator to reuse cached HTTP Basic credentials for authenticated API calls. Requires explicit misconfiguration with wildcard CORS origin and a valid authenticated browser session.

## Affected products

- RabbitMQ RabbitMQ 3.13.0 to 3.13.16, 4.0.0 to 4.0.21, 4.1.0 to 4.1.12, 4.2.0 to 4.2.5

## Timeline

- 2026-07-09: disclosed
- 2026-09-23: patched

## 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/security/advisories/GHSA-p3hp-v9wh-ghm7](https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-p3hp-v9wh-ghm7)

## 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)