CVE-2026-66078: RabbitMQ: protected tag bypass via bulk-delete
RabbitMQ is a messaging and streaming broker. From 3.13.0 until 3.13.15 and 4.0.20 and 4.1.11 and 4.2.6, protected tag bypass via bulk-delete. dELETE /api/users/:name refuses to delete users tagged protected (rabbitmgmtwmuser:deleteresource/2 checks isprotecteduser). POST /api/users/bulk-delete iterates the supplied username list and calls rabbitauthbackendinternal:deleteuser/2 directly , that function has no protected-tag check , so the guard is silently An administrator can delete protected-tagged service accounts via the bulk endpoint, bypassing a safeguard the test suite confirms is rabbitmqmanagement enabled Attacker has the administrator tag A protected-tagged user. This issue is fixed in versions 3.13.15 and 4.0.20 and 4.1.11 and 4.2.6.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
RabbitMQto a version that resolves this vulnerability.Fixed in 3.13.15 - Upgrade
Upgrade
RabbitMQto a version that resolves this vulnerability.Fixed in 4.0.20 - Upgrade
Upgrade
RabbitMQto a version that resolves this vulnerability.Fixed in 4.1.11 - Upgrade
Upgrade
RabbitMQto a version that resolves this vulnerability.Fixed in 4.2.6
Event History
Frequently Asked Questions
Who can exploit this issue?
An attacker must have the RabbitMQ administrator tag and access to the management API. The issue affects deletion of users that have the protected tag.
Is the management plugin required for exploitation?
Yes. The affected bulk-delete API endpoint is part of RabbitMQ Management, and the available information states that rabbitmq_management is enabled.
What action can an administrator take through the vulnerable endpoint?
An administrator can submit protected-tagged usernames to POST /api/users/bulk-delete. Unlike the single-user DELETE endpoint, the bulk-delete path directly calls the internal delete function without enforcing the protected-tag check.
Which versions contain the fix?
The issue is fixed in RabbitMQ 3.13.15, 4.0.20, 4.1.11, and 4.2.6. Affected releases include versions from 3.13.0 up to the listed fixed releases in the applicable release branches.