RabbitMQ: Incomplete fix for CVE-2026-44838: `escape_regex_char/1` does not escape `-`, leaving room for an MQTT topic permission bypass
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.
CVE-2026-67407
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-67407
rabbitmq-server
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "rabbitmq",
"product": "rabbitmq-server",
"versions": [
{
"status": "affected",
"version": ">= 4.3.2, < 4.3.3"
},
{
"status": "affected",
"version": ">= 4.2.0, < 4.2.9"
},
{
"status": "affected",
"version": ">= 4.1.0, < 4.1.14"
},
{
"status": "affected",
"version": ">= 4.0.0, < 4.0.23"
}
]
}
]- Related CVEs
- CVE-2026-67407
Source reference:
/cveMetadata/cveId
Publisher severity
medium
Source reference: /containers/cna/metrics
- Event
- #2206 · Revision 1
- Added to Heist Feed
- Publisher date