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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-42209 Detail

Description

FlashMQ is a MQTT broker/server, designed for multi-CPU environments. Prior to version 1.26.1, a remote client with retained publish permission can crash the FlashMQ broker when both set_retained_message_defer_timeout and set_retained_message_defer_timeout_spread are configured to non-default values, resulting in denial of service. If anonymous retained publishing is allowed, no authentication is required; otherwise, the attacker needs the corresponding publish permission. This issue has been patched in version 1.26.1.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/halfgaar/FlashMQ/commit/193b6e7767889511cfa8e933908ea5e6a1077a1f GitHub, Inc.
https://github.com/halfgaar/FlashMQ/issues/167 GitHub, Inc.
https://github.com/halfgaar/FlashMQ/releases/tag/v1.26.1 GitHub, Inc.
https://github.com/halfgaar/FlashMQ/security/advisories/GHSA-2789-vfcg-5922 GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-369 Divide By Zero GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-42209
NVD Published Date:
05/08/2026
NVD Last Modified:
05/08/2026
Source:
GitHub, Inc.