Totolink A8000RU Command Injection Vulnerability in CGI Handler

A command injection vulnerability has been identified in the Totolink A8000RU router, specifically in the 7.1cu.643_b20200521 version. The issue resides within the CGI handler, in the file '/cgi-bin/cstecgi.cgi', particularly in the 'setNtpCfg' function. This vulnerability allows remote attackers to execute arbitrary operating system commands by manipulating the 'tz' parameter in the HTTP request. The injected commands are executed with root privileges, potentially leading to a full compromise of the router and its connected network.

Impact

Exploitation of this vulnerability allows for arbitrary OS command execution with root privileges on the affected router.

Reproduction

To reproduce this vulnerability, send a POST request to '/cgi-bin/cstecgi.cgi' with the 'tz' parameter set to a crafted command, such as '`ls>./setNtpCfg.txt`'. The router will execute the command and create a text file containing the command's output.