Tenda AC8V4 Stack Overflow Vulnerability in the shareSpeed Parameter

A stack overflow vulnerability has been identified in the Tenda AC8V4 router, specifically in version V16.03.34.06. The issue arises in the sub_47D878 function, where the shareSpeed parameter is improperly handled, leading to potential memory corruption.

Impact

Exploitation of this vulnerability causes a stack overflow, which can lead to arbitrary code execution or a denial-of-service condition by crashing the device.

Reproduction

The vulnerability can be reproduced by sending a crafted request that includes a shareSpeed parameter with a value that exceeds the expected length. This can be done through the router's web interface or by using a network tool to send the malicious payload directly to the device.