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.
Affected products
moquette: moquette
References4
- github.com/moquette-io/moquette/security/advisories/GHSA-5f42-9… ExploitMitigationVendor Advisory
- github.com/moquette-io/moquette/security/advisories/GHSA-5f42-9… ExploitMitigationVendor Advisory
- github.com/moquette-io/moquette/commit/f5a323fe782d1505c0097498… Patch
- github.com/moquette-io/moquette/releases/tag/v0.18.1 Release Notes
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - CVSS 4.0
-
8.7
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 25 · as of 9 November 2026
- CWE
- CWE-862
Could this be exploited in your environment?
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