{"id":"CVE-2026-66070","summary":"RabbitMQ: CORS * reflects Origin with Allow-Credentials","details":"RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.17, 4.0.22, 4.1.13, and 4.2.6, match_origin/1 returned the bare reflected Origin and allowed credentials even when the wildcard \"\" was configured, so the response echoed the attacker's origin together with Access-Control-Allow-Credentials. The affected code is rabbit_mgmt_cors.erl. When the management plugin is configured with a wildcard CORS origin (cors_allow_origins = \"\"), the handler reflects the request Origin back in Access-Control-Allow-Origin and also sends Access-Control-Allow-Credentials: true. A malicious web page that a signed-in administrator visits can then use that administrator's cached HTTP Basic credentials to issue authenticated, state-changing requests to the management API. Preconditions include The management plugin is configured with the wildcard cors_allow_origins = \"*\", which is an explicit operator misconfiguration A target administrator has a cached HTTP Basic-auth session in the browser. This issue is fixed in versions 3.13.17, 4.0.22, 4.1.13, and 4.2.6.","aliases":["GHSA-p3hp-v9wh-ghm7"],"modified":"2026-09-26T03:30:41.645382960Z","published":"2026-09-23T19:59:58.788Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/66xxx/CVE-2026-66070.json","unresolved_ranges":[{"source":"AFFECTED_FIELD","extracted_events":[{"introduced":"3.13.0"},{"fixed":"3.13.17"},{"introduced":"4.0.0"},{"fixed":"4.0.22"},{"introduced":"4.1.0"},{"fixed":"4.1.13"}]}],"cna_assigner":"GitHub_M","cwe_ids":["CWE-942"]},"references":[{"type":"WEB","url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/66xxx/CVE-2026-66070.json"},{"type":"ADVISORY","url":"https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-p3hp-v9wh-ghm7"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-66070"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/rabbitmq/rabbitmq-server","events":[{"introduced":"95c501fbad76c66156346cf364d158d6e30aa4d9"},{"fixed":"8a56c37f099a7bf609a555de3f0ff8ed23964d20"}],"database_specific":{"extracted_events":[{"introduced":"4.2.0"},{"fixed":"4.2.6"}],"source":["AFFECTED_FIELD","REFERENCES"]}}],"versions":["v4.2.5","v4.2.4","v4.2.3","v4.2.2","v4.2.1","v4.2.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-66070.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N"}]}