Reference page — cumulative record through Monday, October 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-67407

CVE-2026-67407MEDIUM

RabbitMQ: Incomplete fix for CVE-2026-44838: `escape_regex_char/1` does not escape `-`, leaving room for an MQTT topic permission bypass

  AV  AC  AT  PR  UI  VC  VI  VA   CVSS    EPSS   %ile   KEV
   N   L   P   L   N   N   N   N    5.1   .0023   12.4     —

AFFECTED
  Product          Versions             Fixed
  rabbitmq-server  >= 4.3.2, < 4.3.3 –  —

TIMELINE
  Jul 29  Reserved by GitHub_M
  Sep 25  Published (CNA: GitHub_M)
  Oct 16  EXPLOIT PUBLISHED — CVE-2026-67407 (rabbitmq-server). Public exploit reference added.

CWE-862 · CNA: GitHub_M · CVSS v4.0 · 3 references · NVD status: Analyzed

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.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
July 29, 2026	Reserved	Reserved by GitHub_M
September 25, 2026	Published	Published (CNA: GitHub_M)
October 16, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-67407 (rabbitmq-server). Public exploit reference added.

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
rabbitmq	rabbitmq-server	—	>= 4.3.2, < 4.3.3	—

Weaknesses

CWE-862

References (3)

https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.9 [Release Notes]
https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.3 [Release Notes]
https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-q46v-hrvq-hp24 [Vendor Advisory, Exploit, Mitigation]

Authoritative record: CVE-2026-67407 at cve.org

Vendors: rabbitmq

Weaknesses: CWE-862

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-67407 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Monday, October 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.