Medium severity · published Sep 23, 2026
CVE-2026-67229
RabbitMQ: Admin-only atom exhaustion: atomize_keys on vhost metadata
4.9
CVSS
0.4%
EPSS
No
On KEV
Description
RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0, add_vhost/2 calls rabbit_data_coercion:atomize_keys/1 (the unsafe variant using binary_to_atom) on the vhost metadata map. The 20 MB management body limit fits ~1M+ short keys. Admin-only. An administrator importing a crafted definitions file can crash the node in a single request: a vhosts entry with ~1M unique metadata keys exhausts the atom table during import. Preconditions include administrator tag. This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 33% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RA
rabbitmq-server · rabbitmq
>= 3.13.0, < 3.13.15; >= 4.0.0, < 4.0.20; >= 4.1.0, < 4.1.11; >= 4.2.0, < 4.2.6 · source: vendor
RS
Rabbitmq Server · Broadcom
3.13.0 before 3.13.15; 4.0.0 before 4.0.20; 4.1.0 before 4.1.11; 4.2.0 before 4.2.6 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-67229
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-67229
Release Notes
https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6
Release Notes
https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.0
Vendor Advisory
https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-ggrw-qm45-hwpv
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