CVE-2026-67420

RabbitMQ is a messaging and streaming broker. From 3.13.0 until 3.13.19, 4.0.24, 4.1.15, 4.2.10, and 4.3.5, RabbitMQ OAuth credential refresh retains revoked runtime tags. when an existing AMQP connection refreshes from an OAuth token that grants the impersonator tag to a valid same-username token that no longer grants that tag, RabbitMQ updates the OAuth backend implementation (token/scopes/expiry) but leaves the connection's runtime #user.tags unchanged. rabbitaccesscontrol:checkuserid/2 then still honors the stale impersonator tag, so the connection (including newly opened channels) can continue publishing messages with a foreign AMQP userid after that privilege should have been revoked. A fresh connection using the downgraded token correctly refuses the same publish, proving the defect is stale session state rather than the token Limited to connections that once held impersonator and successfully refresh to a downgraded same-username rabbitauthbackendoauth2 (or an equivalent refresh-capable backend that returns tags) is enabled for This issue is fixed in versions 3.13.19, 4.0.24, 4.1.15, 4.2.10, and 4.3.5.
Configurations

Configuration 1 (hide)

OR cpe:2.3:a:broadcom:rabbitmq_server:*:*:*:*:*:*:*:*
cpe:2.3:a:broadcom:rabbitmq_server:*:*:*:*:*:*:*:*
cpe:2.3:a:broadcom:rabbitmq_server:*:*:*:*:*:*:*:*
cpe:2.3:a:broadcom:rabbitmq_server:*:*:*:*:*:*:*:*
cpe:2.3:a:broadcom:rabbitmq_server:*:*:*:*:*:*:*:*

History

16 Oct 2026, 15:38

Type Values Removed Values Added
First Time Broadcom rabbitmq Server
Broadcom
CPE cpe:2.3:a:broadcom:rabbitmq_server:*:*:*:*:*:*:*:*
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 6.5
References () https://github.com/rabbitmq/rabbitmq-server/commit/5de287d213765ca592ff5848ad2f6b9b98ee6772 - () https://github.com/rabbitmq/rabbitmq-server/commit/5de287d213765ca592ff5848ad2f6b9b98ee6772 - Patch
References () https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.5 - () https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.5 - Release Notes
References () https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-86fm-44m9-rqjx - () https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-86fm-44m9-rqjx - Vendor Advisory, Mitigation, Exploit

29 Sep 2026, 20:17

Type Values Removed Values Added
References () https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-86fm-44m9-rqjx - () https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-86fm-44m9-rqjx -

25 Sep 2026, 17:17

Type Values Removed Values Added
New CVE

Information

Published : 2026-09-25 17:17

Updated : 2026-10-16 15:38


NVD link : CVE-2026-67420

Mitre link : CVE-2026-67420

CVE.ORG link : CVE-2026-67420


JSON object : View

Products Affected

broadcom

  • rabbitmq_server
CWE
CWE-862

Missing Authorization