{"id":"CVE-2026-67407","published":"2026-09-25T17:17:12.620","lastModified":"2026-09-28T14:38:38.163","description":"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.","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":["CWE-862"],"vendors":[],"products":[],"references":[{"url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.9","tags":[]},{"url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.3","tags":[]},{"url":"https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-q46v-hrvq-hp24","tags":[]}],"exploitRefs":[{"url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.9","tags":[]},{"url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.3","tags":[]},{"url":"https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-q46v-hrvq-hp24","tags":[]}],"hasPoc":true,"ai":null}