CVE-2026-95842: CWE-248: Uncaught Exception in moquette-io moquette
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.
AI Analysis
Technical Summary
Moquette versions before 0.18.1 have a flaw in the SessionEventLoop where only InterruptedException is caught. If an MQTT command triggers an uncaught exception, it terminates the event loop shared by multiple client sessions. Since the SessionEventLoopGroup does not restart terminated loops, this leads to denial of service for all clients mapped to that loop. Attackers can deliberately select client IDs to target specific loops, causing widespread disruption of MQTT session processing. The issue is resolved in version 0.18.1.
Potential Impact
Successful exploitation results in denial of service for multiple MQTT client sessions sharing the same event loop. This prevents processing of critical MQTT commands such as PUBLISH, SUBSCRIBE, and PUBACK, effectively disrupting broker functionality for affected clients. The impact is high as it affects availability of the MQTT broker service.
Mitigation Recommendations
Upgrade moquette to version 0.18.1 or later, where this issue is fixed. No other mitigations are indicated. Patch status is confirmed fixed in 0.18.1.
CVE-2026-95842: CWE-248: Uncaught Exception in moquette-io moquette
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.
CVSS v4.0
Score 8.7high
Affected software
moquette-io
moquette
pkg:github/moquette-io/moquetteRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Moquette versions before 0.18.1 have a flaw in the SessionEventLoop where only InterruptedException is caught. If an MQTT command triggers an uncaught exception, it terminates the event loop shared by multiple client sessions. Since the SessionEventLoopGroup does not restart terminated loops, this leads to denial of service for all clients mapped to that loop. Attackers can deliberately select client IDs to target specific loops, causing widespread disruption of MQTT session processing. The issue is resolved in version 0.18.1.
Potential Impact
Successful exploitation results in denial of service for multiple MQTT client sessions sharing the same event loop. This prevents processing of critical MQTT commands such as PUBLISH, SUBSCRIBE, and PUBACK, effectively disrupting broker functionality for affected clients. The impact is high as it affects availability of the MQTT broker service.
Mitigation Recommendations
Upgrade moquette to version 0.18.1 or later, where this issue is fixed. No other mitigations are indicated. Patch status is confirmed fixed in 0.18.1.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-09-22T16:39:45.793Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ab402daf7a7c541060ee0d0
Added to database: 09/23/2026, 16:48:26 UTC
Last enriched: 09/23/2026, 17:03:55 UTC
Last updated: 09/24/2026, 02:15:07 UTC
Views: 8
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