{"id":"CVE-2026-67409","title":"RabbitMQ is a messaging and streaming broker","summary":"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 …","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-252"],"vendor":"broadcom","product":"rabbitmq_server","affected":["rabbitmq_server >= 3.13.0, < 3.13.18","rabbitmq_server >= 4.0.0, < 4.0.23","rabbitmq_server >= 4.1.0, < 4.1.14","rabbitmq_server >= 4.2.0, < 4.2.9","rabbitmq_server >= 4.3.0, < 4.3.3"],"patched":["rabbitmq_server 4.3.3"],"published":"2026-09-25","updated":"2026-10-08","sourceUpdated":"2026-10-08T15:36:44.860","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-67409","references":[{"url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.9","label":"security-advisories@github.com"},{"url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.3","label":"security-advisories@github.com"},{"url":"https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-qw3h-qqm9-jrw8","label":"security-advisories@github.com"},{"url":"https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-qw3h-qqm9-jrw8","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-67409.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-67409"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2541514"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-67409"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-67409"},{"url":"https://access.redhat.com/errata/RHSA-2026:67552"}],"tags":["nvd","cve.org","exploit-available","csaf","vex","red-hat"],"epss":0.00418,"epssPercentile":0.35913,"exploitAvailable":true,"ssvc":{"exploitation":"poc","automatable":"no","technicalImpact":"partial","timestamp":"2026-09-25T17:49:17.770463Z"},"scores":{"nvd":6.5,"cna":8.2,"vendor":7.5},"ingestedAt":"2026-09-25T17:13:14.025Z","slug":"CVE-2026-67409","body":"## Overview\n\nRabbitMQ 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.\n\n## Affected\n\n- `rabbitmq_server >= 3.13.0, < 3.13.18`\n- `rabbitmq_server >= 4.0.0, < 4.0.23`\n- `rabbitmq_server >= 4.1.0, < 4.1.14`\n- `rabbitmq_server >= 4.2.0, < 4.2.9`\n- `rabbitmq_server >= 4.3.0, < 4.3.3`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `rabbitmq_server 4.3.3`\n\n## Vendor advisories\n\n- **RHSA-2026:67552** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-09-15 · [advisory](https://access.redhat.com/errata/RHSA-2026:67552)\n- **Red Hat VEX** · Important · affected: Red Hat Hardened Images · no fix planned: Red Hat Hardened Images · updated 2026-10-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-67409.json)","depth":"twilight","depthScore":48,"depthScoreParts":{"impact":35.8,"likelihood":0.1,"exploitation":12,"ransomware":0},"changes":[{"seq":218070,"id":"CVE-2026-67409","ts":1791474625269,"field":"cvss","old":"8.2","new":"6.5"},{"seq":218069,"id":"CVE-2026-67409","ts":1791474625269,"field":"severity","old":"high","new":"medium"},{"seq":211107,"id":"CVE-2026-67409","ts":1790360106425,"field":"exploit_available","old":"false","new":"true"}]}