# CVE-2026-67223: RabbitMQ LDAP DN injection in auth backend

Source: https://junglewise.ai/threats/cve-2026-67223-rabbitmq-is-a-messaging-and-streaming-broker-the-advisory  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-25. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-67223 · Severity: info · Published 2026-09-25

RabbitMQ is a message broker that supports LDAP authentication. When using the LDAP auth backend with a pattern to construct directory bind names, RabbitMQ fails to properly escape special characters in usernames, allowing an attacker to craft a username that alters the LDAP search and potentially authenticate as a different user. Successful exploitation requires LDAP to be configured with a pattern containing the username placeholder and a directory layout where the injected suffix maps to a valid account.

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

## Quick answers

**Is CVE-2026-67223 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-67223 being exploited in the wild.

**How severe is CVE-2026-67223?** Informational severity, published 25 September 2026.

**Which products and versions are affected?** RabbitMQ 3.13 before 3.13.15, 4.0 before 4.0.20, 4.1 before 4.1.11, 4.2 before 4.2.9, 4.3 before 4.3.3.

**Is there a fix for CVE-2026-67223?** A patch was published on 2026-04-14: fix commit authored; released in versions 3.13.15, 4.0.20, 4.1.11, 4.2.9, 4.3.3 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-67223 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-67223?** 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 rabbitmq_auth_backend_ldap module substitutes ${username} into user_dn_pattern without applying RFC 4514 DN escaping, allowing LDAP DN injection. An attacker with a valid password for any account can craft a username that injects DN components to alter bind targets. The fill/2 function was replaced with fill_dn/2 to properly escape template values per RFC 4514, mitigating username-based DN manipulation.

## Affected products

- RabbitMQ RabbitMQ 3.13 before 3.13.15, 4.0 before 4.0.20, 4.1 before 4.1.11, 4.2 before 4.2.9, 4.3 before 4.3.3

## Timeline

- 2026-09-25: disclosed
- 2026-04-14: patched: fix commit authored; released in versions 3.13.15, 4.0.20, 4.1.11, 4.2.9, 4.3.3

## References

- [https://github.com/rabbitmq/rabbitmq-server/commit/ad3ca47accd313a4a0dbcbbe17bf60fc8f4b2614](https://github.com/rabbitmq/rabbitmq-server/commit/ad3ca47accd313a4a0dbcbbe17bf60fc8f4b2614)
- [https://github.com/rabbitmq/rabbitmq-server/commit/b54056e59b7fd3a2d7f07dfaba95f026e138eee8](https://github.com/rabbitmq/rabbitmq-server/commit/b54056e59b7fd3a2d7f07dfaba95f026e138eee8)

## 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)