High severity · published Sep 23, 2026
CVE-2026-95846
Moquette publishes Last-Will messages without enforcing write authorization
7.5
CVSS
0.3%
EPSS
No
On KEV
Description
Moquette is a lightweight Java MQTT broker. Prior to 0.18.1, PostOffice.publishWill publishes a client's Last-Will message without applying the canWrite authorization and reserved-topic checks used for a normal PUBLISH. A client can configure a Will for a topic that the client is not permitted to write and cause the broker to publish the unauthorized message when the client disconnects unexpectedly. This issue allows unauthorized message injection into restricted topics. This issue is fixed in version 0.18.1.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 25% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MO
moquette · moquette-io
< 0.18.1 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-95846
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-95846
Patch
https://github.com/moquette-io/moquette/commit/f5a323fe782d1505c0097498cb22eb6ec6c96973
Release Notes
https://github.com/moquette-io/moquette/releases/tag/v0.18.1
Exploit
https://github.com/moquette-io/moquette/security/advisories/GHSA-5f42-97gr-vfhq
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