TOTOLINK X5000R OS Command Injection Vulnerability in setVpnAccountCfg

An OS command injection vulnerability has been identified in the TOTOLINK X5000R router, specifically in firmware version V9.1.0cu.2350_B20230313. The vulnerability arises in the 'setVpnAccountCfg' function within the '/web/cgi-bin/cstecgi.cgi' file. Authenticated attackers can exploit this issue by sending crafted requests that include malicious commands, which are then executed on the device.

Impact

Exploitation of this vulnerability allows authenticated attackers to execute arbitrary commands on the router's operating system.

Reproduction

To reproduce this vulnerability, send a POST request to '/cgi-bin/cstecgi.cgi' with the 'limit' parameter containing a malicious command. The request must include authentication tokens and be sent as an XMLHttpRequest. The crafted command will be executed on the device, demonstrating the OS command injection flaw.