{"id":"CVE-2026-67407","summary":"RabbitMQ: Incomplete fix for CVE-2026-44838: `escape_regex_char/1` does not escape `-`, leaving room for an MQTT topic permission bypass","details":"RabbitMQ is a messaging and streaming broker. From 4.0.0 until 4.3.3 and 4.2.9 and 4.1.14 and 4.0.23, Incomplete fix for CVE-2026-44838: escaperegexchar/1 does not escape -, leaving room for an MQTT topic permission bypass. the CVE-2026-44838 fix made expandtopicpermission/2 escape regex metacharacters in expanded topic-permission variables (escaperegex(V)), but escaperegexchar/1 escapes \\ ^ $ . | ? + ( ) [ ] { } and omits -. When a topic permission template places {clientid} inside a [...] character class A low-privileged authenticated MQTT user controlling its clientid can broaden topic authorization (read and write) when templates embed {clientid} in a [...] This issue is fixed in versions 4.3.3 and 4.2.9 and 4.1.14 and 4.0.23.","aliases":["GHSA-q46v-hrvq-hp24"],"modified":"2026-09-27T03:47:29.307384706Z","published":"2026-09-25T16:30:35.252Z","database_specific":{"unresolved_ranges":[{"extracted_events":[{"introduced":"4.1.0"},{"fixed":"4.1.14"},{"introduced":"4.0.0"},{"fixed":"4.0.23"}],"source":"AFFECTED_FIELD"}],"cna_assigner":"GitHub_M","cwe_ids":["CWE-862"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/67xxx/CVE-2026-67407.json"},"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":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/67xxx/CVE-2026-67407.json"},{"type":"ADVISORY","url":"https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-q46v-hrvq-hp24"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-67407"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/rabbitmq/rabbitmq-server","events":[{"introduced":"a509158b1b1e21c892a7f1dacbe0d158076dc7b8"},{"introduced":"95c501fbad76c66156346cf364d158d6e30aa4d9"},{"fixed":"1d284b2d2a1e2f845ad22b0d5ee38ec372d50802"},{"fixed":"47d6d6457c7d1a440daed643cb7d76bba313e79c"}],"database_specific":{"source":["AFFECTED_FIELD","REFERENCES"],"extracted_events":[{"introduced":"4.3.2"},{"fixed":"4.3.3"},{"introduced":"4.2.0"},{"fixed":"4.2.9"}]}}],"versions":["v4.2.8","v4.3.2","v4.2.7","v4.2.6","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-2026-67407.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:H/SA:N"}]}