Tenda AC9 Stack Overflow Vulnerability in wanSpeed Parameter Allows Remote Code Execution

A stack overflow vulnerability has been identified in the Tenda AC9 router, specifically in version 1.0 with firmware V15.03.05.14_multi. The issue arises in the wanSpeed parameter of the /goform/AdvSetMacMtuWan endpoint, where improper handling of data can lead to a buffer overflow. This vulnerability allows for remote arbitrary code execution on the affected device.

Impact

Exploitation of this vulnerability allows for remote arbitrary code execution on the affected router.

Reproduction

To reproduce this vulnerability, send a POST request to the /goform/AdvSetMacMtuWan endpoint. Include a crafted wanSpeed parameter with a payload designed to overflow the stack. The overflow can be exploited to execute arbitrary code remotely on the device.