CVE-2026-67407 (GCVE-0-2026-67407)

Vulnerability from cvelistv5 – Published: 2026-09-25 16:30 – Updated: 2026-09-25 17:20
VLAI
Title
RabbitMQ: Incomplete fix for CVE-2026-44838: `escape_regex_char/1` does not escape `-`, leaving room for an MQTT topic permission bypass
Summary
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.
Severity
5.1 (Medium)
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-25 17:20 UTC
CWE
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8062 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
rabbitmq rabbitmq-server Affected: >= 4.3.2, < 4.3.3
Affected: >= 4.2.0, < 4.2.9
Affected: >= 4.1.0, < 4.1.14
Affected: >= 4.0.0, < 4.0.23
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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