Description
Moquette is a lightweight Java MQTT broker. Prior to 0.18.1, SessionEventLoop.run catches only InterruptedException, and SessionEventLoopGroup does not restart a terminated loop. An MQTT command that raises an uncaught exception can terminate an event loop shared by multiple client sessions, preventing every co-located client from processing PUBLISH, SUBSCRIBE, PUBACK, and other commands. An attacker can select client IDs that map across the available loops to disrupt session processing for the entire broker. This issue is fixed in version 0.18.1.
Affected products
moquette: moquette
References5
- 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/86feb7c31e6fac849c465d80… Patch
- github.com/moquette-io/moquette/pull/957 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:N/A:H - 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:N/VA:H/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: 38 · as of 9 November 2026
- CWE
- CWE-248
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.