All vulnerabilities
CVE-2026-67409GHSA-qw3h-qqm9-jrw8

rabbitmq-server: RabbitMQ: JWKS Fetch Ignores HTTP Response Status Code - Signing Key Destruction Causes Authentication DoS

rabbitmq rabbitmq-server
CVSS
8.2High
ExploitationPublic exploit codeCISA's assessment says proof of concept code is public, assessed 25 Sep 2026. Not in the KEV catalogCISA via CVE List
Exploit odds (EPSS)0.42%Chance of exploitation activity in the next 30 days, higher than 35% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in4.3.3Also 4.2.9, 4.1.14 and 2 moreGitHub
Published25 Sep 2026Updated 25 Sep 2026CVE List

What fixes it

  • 4.3.3rabbitmq-server, rabbitmqGitHub
  • 4.2.9rabbitmq-server, rabbitmqGitHub
  • 4.1.14rabbitmq-server, rabbitmqGitHub
  • 4.0.23rabbitmq-server, rabbitmqGitHub
  • 3.13.18rabbitmq-server, rabbitmqGitHub

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 4.3.3, 4.2.9, 4.1.14, 4.0.23, and 3.13.18, JWKS Fetch Ignores HTTP Response Status Code - Signing Key Destruction Causes Authentication DoS (CWE-252). the JWKS key fetching mechanism in uaajwt.erl does not validate the HTTP response status code when downloading signing keys from the OAuth2 provider's JWKS endpoint. Non-200 responses (including 4xx and 5xx errors) are processed identically to successful responses. When the JWKS endpoint returns an error response with a valid-JSON body that lacks a keys field, all previously cached signing keys are destroyed, causing a persistent authentication denial of Files: deps/rabbitmqauthbackendoauth2/src/uaajwt.erl, lines 50-63 deps/rabbitmqauthbackendoauth2/src/uaajwks.erl, lines 5-7 deps/rabbitmqauthbackendoauth2/src/rabbitoauth2provider.erl, lines 98-107 Bug 1: HTTP status code ignored (uaajwt.erl:50-63): The Erlang httpc module returns {ok, {{HttpVersion, StatusCode, ReasonPhrase}, Headers, Body}}. The pattern {ok, {, , JwksBody}} matches ANY successful HTTP transaction Persistent authentication DoS: Once keys are destroyed, ALL OAuth2/JWT authentication fails for all users until a new successful JWKS refresh occurs Amplification: A single attacker can deny access to all legitimate OAuth2 users across the entire RabbitMQ. This issue is fixed in versions 4.3.3, 4.2.9, 4.1.14, 4.0.23, and 3.13.18.

Text from CVE List

Affected versions 10

  • rabbitmq-serveraffected: >= 4.3.0, < 4.3.3CVE List
  • rabbitmq-serveraffected: >= 4.2.0, < 4.2.9CVE List
  • rabbitmq-serveraffected: >= 4.1.0, < 4.1.14CVE List
  • rabbitmq-serveraffected: >= 4.0.0, < 4.0.23CVE List
  • rabbitmq-serveraffected: >= 3.13.0, < 3.13.18CVE List
  • rabbitmq-server, rabbitmq>= 4.3.0, < 4.3.3GitHub
  • rabbitmq-server, rabbitmq>= 4.2.0, < 4.2.9GitHub
  • rabbitmq-server, rabbitmq>= 4.1.0, < 4.1.14GitHub
  • rabbitmq-server, rabbitmq>= 4.0.0, < 4.0.23GitHub
  • rabbitmq-server, rabbitmq>= 3.13.0, < 3.13.18GitHub

References 3