{"id":"BIT-rabbitmq-2026-67409","summary":"RabbitMQ: JWKS Fetch Ignores HTTP Response Status Code - Signing Key Destruction Causes Authentication DoS","details":"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.","aliases":["CVE-2026-67409","GHSA-qw3h-qqm9-jrw8"],"modified":"2026-10-01T10:10:49.330038164Z","published":"2026-10-01T09:33:49.456Z","database_specific":{"severity":"High","cpes":["cpe:2.3:a:vmware:rabbitmq:*:*:*:*:*:*:*:*"]},"references":[{"type":"WEB","url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.9"},{"type":"WEB","url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.3"},{"type":"WEB","url":"https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-qw3h-qqm9-jrw8"},{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-67409"}],"affected":[{"package":{"name":"rabbitmq","ecosystem":"Bitnami","purl":"pkg:bitnami/rabbitmq"},"ranges":[{"type":"SEMVER","events":[{"introduced":"3.13.0"},{"fixed":"3.13.18"},{"introduced":"4.0.0"},{"fixed":"4.0.23"},{"introduced":"4.1.0"},{"fixed":"4.1.14"},{"introduced":"4.2.0"},{"fixed":"4.2.9"},{"introduced":"4.3.0"},{"fixed":"4.3.3"}]}],"database_specific":{"source":"https://github.com/bitnami/vulndb/tree/main/data/rabbitmq/BIT-rabbitmq-2026-67409.json"},"severity":[{"type":"CVSS_V4","score":"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"}]}],"schema_version":"1.9.0"}