{"id":"CVE-2026-67409","revision":"628461c55b4b4a1ead47fa8661d02fd9","records":[{"revision":"628461c55b4b4a1ead47fa8661d02fd9","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-67409","aliases":[],"title":"RabbitMQ: JWKS Fetch Ignores HTTP Response Status Code - Signing Key Destruction Causes Authentication DoS","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.","state":0,"publishedAt":"2026-09-25T16:18:25.611+00:00","modifiedAt":"2026-09-25T17:49:48.064+00:00","affected":[{"ecosystem":"Vendor product","name":"rabbitmq-server","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"rabbitmq\",\n                    \"product\": \"rabbitmq-server\",\n                    \"versions\": [\n                        {\n                            \"version\": \">= 4.3.0, < 4.3.3\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \">= 4.2.0, < 4.2.9\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \">= 4.1.0, < 4.1.14\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \">= 4.0.0, < 4.0.23\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \">= 3.13.0, < 3.13.18\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","score":8.2,"severity":"HIGH"}],"references":["https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-qw3h-qqm9-jrw8","https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.9","https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.3"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-67409","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-67409","identifiers":["CVE-2026-67409"]},"retained":false,"historicalAffected":[]}],"coverage":[]}