CVE-2026-67226

RabbitMQ: Admin-only atom exhaustion: PUT /api/users tags list

State: Published
Severity: 6.9 Medium
Published: Sep 25, 2026
Updated: Sep 25, 2026
Reserved: Jul 28, 2026

Description

RabbitMQ is a messaging and streaming broker. From 4.0.0 until 4.0.22 and 4.1.14 and 4.2.7, Admin-only atom exhaustion: PUT /api/users tags list. settags/2 maps rabbitdatacoercion:toatom/1 over the user's tags list. The 20 MB management body limit fits ~3-4M short tag strings. An administrator can crash the node in a single request by creating a user (or importing definitions) with ~1M unique tag administrator. This issue is fixed in versions 4.0.22 and 4.1.14 and 4.2.7.

Scores

CVSS	Score	Vector	Source
4.0	6.9 Medium	CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N	GitHub_M

Weaknesses

CWE-400 Uncontrolled Resource Consumption

Affected Products

Product	Versions
rabbitmq-serverrabbitmq	>= 4.0.0, < 4.0.22Affected >= 4.1.0, < 4.1.14Affected >= 4.2.0, < 4.2.7Affected

References

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