CVE-2026-101003: Stack-based Buffer Overflow in Cesanta Mongoose
A weakness has been identified in Cesanta Mongoose up to 7.21. Affected by this vulnerability is the function fn of the file tutorials/mqtt/mqtt-server/main.c of the component MQTT Broker. Executing a manipulation can lead to stack-based buffer overflow. The attack can be launched remotely. The exploit has been made available to the public and could be used for attacks. Upgrading to version 7.22 addresses this issue. This patch is called a9df523f76f43a38bd53b4232b9cfd4c16869e71. Upgrading the affected component is advised.
AI Analysis
Technical Summary
A stack-based buffer overflow vulnerability has been identified in Cesanta Mongoose up to version 7.21, specifically in the MQTT Broker component's function 'fn' located in tutorials/mqtt/mqtt-server/main.c. This vulnerability allows remote attackers to cause a buffer overflow by sending manipulated input, potentially leading to arbitrary code execution or denial of service. The vulnerability has a CVSS 4.0 base score of 6.9 (medium severity). The vendor has released a patch in version 7.22 (commit a9df523f76f43a38bd53b4232b9cfd4c16869e71) that addresses this issue.
Potential Impact
Successful exploitation of this vulnerability can lead to a stack-based buffer overflow, which may allow remote attackers to execute arbitrary code or crash the MQTT Broker component. The vulnerability is exploitable remotely without any privileges or user interaction. Public exploit code is available, increasing the risk of attacks.
Mitigation Recommendations
Upgrade Cesanta Mongoose to version 7.22 or later, which contains the official fix for this vulnerability. No other mitigation is indicated or required as the patch fully addresses the issue.
CVE-2026-101003: Stack-based Buffer Overflow in Cesanta Mongoose
Description
A weakness has been identified in Cesanta Mongoose up to 7.21. Affected by this vulnerability is the function fn of the file tutorials/mqtt/mqtt-server/main.c of the component MQTT Broker. Executing a manipulation can lead to stack-based buffer overflow. The attack can be launched remotely. The exploit has been made available to the public and could be used for attacks. Upgrading to version 7.22 addresses this issue. This patch is called a9df523f76f43a38bd53b4232b9cfd4c16869e71. Upgrading the affected component is advised.
CVSS v4.0
Score 6.9medium
Affected software
Cesanta
Mongoose
pkg:github/cesanta/mongoosecpe:2.3:a:cesanta:mongoose:*:*:*:*:*:*:*:*Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
A stack-based buffer overflow vulnerability has been identified in Cesanta Mongoose up to version 7.21, specifically in the MQTT Broker component's function 'fn' located in tutorials/mqtt/mqtt-server/main.c. This vulnerability allows remote attackers to cause a buffer overflow by sending manipulated input, potentially leading to arbitrary code execution or denial of service. The vulnerability has a CVSS 4.0 base score of 6.9 (medium severity). The vendor has released a patch in version 7.22 (commit a9df523f76f43a38bd53b4232b9cfd4c16869e71) that addresses this issue.
Potential Impact
Successful exploitation of this vulnerability can lead to a stack-based buffer overflow, which may allow remote attackers to execute arbitrary code or crash the MQTT Broker component. The vulnerability is exploitable remotely without any privileges or user interaction. Public exploit code is available, increasing the risk of attacks.
Mitigation Recommendations
Upgrade Cesanta Mongoose to version 7.22 or later, which contains the official fix for this vulnerability. No other mitigation is indicated or required as the patch fully addresses the issue.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulDB
- Date Reserved
- 2026-09-27T10:29:14.330Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ab9ffa5f7a7c5410639b3ca
Added to database: 09/28/2026, 05:48:21 UTC
Last enriched: 09/28/2026, 06:02:41 UTC
Last updated: 09/29/2026, 02:42:01 UTC
Views: 20
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