{"id":"BIT-rabbitmq-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":["CVE-2026-67407","GHSA-q46v-hrvq-hp24"],"modified":"2026-10-01T10:10:45.308146327Z","published":"2026-10-01T09:33:46.619Z","database_specific":{"severity":"Medium","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-q46v-hrvq-hp24"},{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-67407"}],"affected":[{"package":{"name":"rabbitmq","ecosystem":"Bitnami","purl":"pkg:bitnami/rabbitmq"},"ranges":[{"type":"SEMVER","events":[{"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":"4.3.2"},{"fixed":"4.3.3"}]}],"database_specific":{"source":"https://github.com/bitnami/vulndb/tree/main/data/rabbitmq/BIT-rabbitmq-2026-67407.json"},"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/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"}