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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| rabbitmq | rabbitmq-server | >= 4.0.0, < 4.0.22, >= 4.1.0, < 4.1.14, >= 4.2.0, < 4.2.7 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | rabbitmq-server | 4.3.0-2 | — |
| Debian 13 | rabbitmq-server | No fix yet | — |
| Debian 12 | rabbitmq-server | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.04 LTS | rabbitmq-server | No fix yet | — |
| Ubuntu 24.04 LTS | rabbitmq-server | No fix yet | — |
| Ubuntu 22.04 LTS | rabbitmq-server | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | rabbitmq-server | No fix yet | — |
| Ubuntu Pro 18.04 LTS | rabbitmq-server | No fix yet | — |
| Ubuntu Pro 16.04 LTS | rabbitmq-server | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat Hardened Images 1 | rabbitmq-server4.3 | 4.3.6-1.hum1 | RHSA-2026:67552 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | rabbitmq-server | 3.13.7-10 | — |
Advisories 2
- RHSA-2026:67552 Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update Red Hat Security Advisories (RHSA) · Nov 13, 2026
- WID-SEC-2026-2485 RabbitMQ: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 4, 2026