What’s Vulnerable › Vulnerabilities

CVE-2026-101003: Cesanta Mongoose MQTT Broker main.c fn stack-based overflow

• Severity: medium (CVSS 5.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-28 · updated 2026-10-01
• Weakness: CWE-119

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.

Affected products

• Cesanta Mongoose: 7.0, 7.1, 7.2, 7.3, 7.4, 7.5 (+16)

References

• https://github.com/cesanta/mongoose/
• https://github.com/cesanta/mongoose/commit/a9df523f76f43a38bd53b4232b9cfd4c16869e71
• https://github.com/cesanta/mongoose/releases/tag/7.22
• https://vuldb.com/cve/CVE-2026-101003
• https://vuldb.com/submit/920005
• https://vuldb.com/vuln/410873
• https://vuldb.com/vuln/410873/cti

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