Unauthorized Message Injection in Moquette MQTT Broker
CVE-2026-95846

8.7HIGH

Key Information:

Vendor

Moquette-io

Status
Moquette
Vendor
CVE Published:
23 September 2026

What is CVE-2026-95846?

The Moquette MQTT Broker is affected by a vulnerability where the PostOffice.publishWill method fails to enforce proper authorization checks. Prior to version 0.18.1, this allowed clients to publish Last-Will messages to topics for which they lacked write permissions. As a consequence, an attacker could exploit this oversight to inject unauthorized messages upon unexpected client disconnection, potentially breaching the intended access controls and compromising the integrity of restricted topics. This issue has been resolved in version 0.18.1, making it imperative for users to upgrade to ensure secure operations.

Affected Version(s)

moquette < 0.18.1

References

https://github.com/moquette-io/moquette/security/advisori...
x_refsource_CONFIRM
https://github.com/moquette-io/moquette/commit/f5a323fe78...
x_refsource_MISC
https://github.com/moquette-io/moquette/releases/tag/v0.18.1
x_refsource_MISC

CVSS V4

Score:
8.7
Severity:
HIGH
Confidentiality:
None
Integrity:
High
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.