Totolink A7100RU Command Injection Vulnerability in CGI Handler

A command injection vulnerability has been identified in the Totolink A7100RU router, specifically in the 7.4cu.2313_b20191024 version. The issue arises within the CGI handler, in a function called setWiFiBasicCfg, located in the file /cgi-bin/cstecgi.cgi. This vulnerability allows remote attackers to execute arbitrary operating system commands by manipulating the wifiOff parameter in a crafted HTTP request. The injected commands are executed with root privileges, potentially compromising the router and the connected network.

Impact

Exploitation of this vulnerability allows for arbitrary OS command execution with root privileges on the affected router. This could lead to a complete compromise of the device and potentially the network it is connected to.

Reproduction

To reproduce this vulnerability, send a POST request to the /cgi-bin/cstecgi.cgi endpoint with the addEffect parameter set to '1' and the wifiOff parameter containing the desired command, such as 'wget' to download a file from a remote server. The router will execute the injected command in the system's command line interface.