All vulnerabilities
CVE-2026-67222GHSA-85jr-6rr2-j73r

rabbitmq-server: RabbitMQ: list_to_atom on auth_mechanism URI tokens in amqp_client

rabbitmq rabbitmq-server
Open in ThreatlineRecord JSON
CVSS
5.9Medium
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.32%Chance of exploitation activity in the next 30 days, higher than 23% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in3.13.15Also 4.0.20, 4.1.11 and 1 moreGitHub
Published25 Sep 2026Updated 28 Sep 2026CVE List

What fixes it

  • 3.13.15amqp_client, erlangGitHub
  • 4.0.20amqp_client, erlangGitHub
  • 4.1.11amqp_client, erlangGitHub
  • 4.2.6amqp_client, erlangGitHub

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

RabbitMQ is a messaging and streaming broker. From 3.13.0 until 3.13.15, 4.0.20, 4.1.11, and 4.2.6, mechanisms/1 applied list_to_atom/1 to every colon-delimited token in an attacker-controlled auth_mechanism value, permanently consuming Erlang VM atoms and allowing the node to be crashed with a large request. Exploitation requires the Shovel or Federation plugin to be in use, and setting auth_mechanism requires the policymaker tag. This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6.

Text from CVE List

Affected versions 8

  • rabbitmq-serveraffected: >= 3.13.0, < 3.13.15CVE List
  • rabbitmq-serveraffected: >= 4.0.0, < 4.0.20CVE List
  • rabbitmq-serveraffected: >= 4.1.0, < 4.1.11CVE List
  • rabbitmq-serveraffected: >= 4.2.0, < 4.2.6CVE List
  • amqp_client, erlang>= 3.13.0, < 3.13.15GitHub
  • amqp_client, erlang>= 4.0.0, < 4.0.20GitHub
  • amqp_client, erlang>= 4.1.0, < 4.1.11GitHub
  • amqp_client, erlang>= 4.2.0, < 4.2.6GitHub

References 2