Tenda CH22 Buffer Overflow Vulnerability in the Command Execution Function

A buffer overflow vulnerability has been identified in the Tenda CH22 router, specifically in the firmware version 1.0.0.1. The issue arises within the 'formexeCommand' function of the '/goform/exeCommand' file, where the 'cmdinput' parameter can be manipulated, leading to a stack overflow. This vulnerability can be exploited remotely, causing the router to become unresponsive and inaccessible.

Impact

Exploitation of this vulnerability causes a stack overflow, disrupting the router's normal operation and rendering it inaccessible.

Reproduction

The vulnerability can be reproduced by sending a POST request to the '/goform/exeCommand' endpoint with a 'cmdinput' parameter that is excessively long, such as 512 bytes of repeated characters. This can be done using a Python script that utilizes the 'requests' library to automate the process.