{"id":"CVE-2026-67407","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-67407","generatedAt":"2026-10-28T01:19:37.331Z","title":"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…","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.","published":"2026-09-25T17:17:13.000Z","lastModified":"2026-10-16T16:10:41.000Z","status":"Analyzed","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"4.0","score":5.1,"severity":"MEDIUM","vector":"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/M"},"cwe":["CWE-862"],"affected":["broadcom/rabbitmq server"],"epss":{"score":0.00263,"percentile":0.17976,"date":"2026-10-26","history":[{"date":"2026-09-26","score":0.00253,"percentile":0.15037}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.26%). Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"new","label":"New CVE","at":"2026-09-25T17:17:13.000Z","detail":{"score":"5.1","severity":"MEDIUM","publishedAt":"2026-09-25T17:17:12.620Z"},"summary":"New CVE, medium severity (CVSS 5.1)."}],"references":[{"url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.9","tags":["Release Notes"],"source":"security-advisories@github.com"},{"url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.3","tags":["Release Notes"],"source":"security-advisories@github.com"},{"url":"https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-q46v-hrvq-hp24","tags":["Vendor Advisory","Exploit","Mitigation"],"source":"security-advisories@github.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-67407","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}