TOTOLINK N600R Buffer Overflow Vulnerability in HTTP Request Handler

A buffer overflow vulnerability has been identified in the TOTOLINK N600R wireless router, affecting firmware versions through 4.3.0cu.7866_B20220506. The vulnerability resides in the HTTP request handler, specifically within the setWiFiBasicConfig function of the cstecgi.cgi file. When the wepkey parameter is supplied with excessive data, a buffer overflow occurs, potentially allowing remote attackers to execute arbitrary code or cause a denial-of-service condition.

Impact

Exploitation of this vulnerability leads to a buffer overflow, which can commonly result in arbitrary code execution or causing a denial-of-service condition on the device.

Reproduction

The vulnerability can be reproduced by sending an HTTP request to the router's cgi-bin endpoint with a crafted wepkey parameter that exceeds the buffer size. This can be done using a proof-of-concept script that automates the process, as detailed in the vulnerability's GitHub advisory.