# CVE-2026-67227: RabbitMQ: Atom exhaustion: to_atom on global-parameter :name

CVE-2026-67227 is fixed in rabbitmq-server on 1 platform by DEBIAN-CVE-2026-67227 (version 4.3.2-1), released September 26, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-67227
- Priority: Routine
- CVSS: 4.9 (Moderate)
- EPSS: 0.0038
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 25, 2026
- Weakness: Uncontrolled Resource Consumption
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-67227

## Description

RabbitMQ is a messaging and streaming broker. From 4.0.0 until 4.0.22 and 4.1.14 and 4.2.7 and 4.3.1, Atom exhaustion: toatom on global-parameter :name. resourceexists/2 (and the PUT/DELETE handlers) call rabbitdatacoercion:toatom/1 on the :name URL path segment. toatom/1 uses binarytoatom/2 (unsafe). The endpoint requires policymaker (not management, but below A user with the policymaker tag can crash the node by exhausting the atom table via repeated requests to /api/global-parameters/:name with unique :name Management plugin enabled policymaker tag ~1M HTTP. This issue is fixed in versions 4.0.22 and 4.1.14 and 4.2.7 and 4.3.1.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | rabbitmq-server Debian 14 | 4.3.2-1 | [DEBIAN-CVE-2026-67227](https://patchblox.com/security/data/fix/linux/debian-cve-2026-67227.md) | Sep 26, 2026 |

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Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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