CVE-2026-114550highCWE-787

CVE-2026-114550: high-severity vulnerability in libwebsockets

libwebsockets MQTT Protocol PUBACK Packet Handling Out-Of-Bounds Write Remote Code Execution Vulnerability

Published · Updated

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41Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 8.1epss 0.8%
from disclosure to weapon2 days
Published on NVDNov 3
1st PoC+2d
libwebsockets MQTT Protocol PUBACK Packet Handling Out-Of-Bounds Write Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of libwebsockets. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of PUBACK packets. The issue results from the lack of proper validation of user-supplied data, which can result in a write past the end of an allocated buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-31039.
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
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