[ CVE-2026-114550 · Published 4 Nov 2026 ]
Vulnerability in libwebsockets
[ Description ]Official description
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.
[ Fixes ]Fixes and patches
No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.