Vulnerability CVE-2018-19988

In the /HNAP1/SetClientInfoDemo message, the AudioMute and AudioEnable parameters are vulnerable, and the vulnerabilities affect D-Link DIR-868L Rev.B 2.05B02 devices. In the SetClientInfoDemo.php source code, the AudioMute and AudioEnble parameters are saved in the ShellPath script file without any regex checking. After the script file is executed, the command injection occurs. It needs to bypass the wget command option with a single quote. A vulnerable /HNAP1/SetClientInfoDemo XML message could have single quotes and backquotes in the AudioMute or AudioEnable element, such as the '`telnetd`' string.