Here we need to find something hidden on host http://10.100.0.1/ using given openvpn configs and dump.
We connected to VPN with given configs but system is required to authenticate. After using strings on dump we got login and password SuperPuperRoot / VeryStrongSecret. So we have authenticated in VPN and went on http://10.100.0.1/. There is we got a page with this source code:
<html> <body> <h1>It works!</h1> <p>This is the default web page for this server.</p> <p>The web server software is running but no content has been added, yet.</p> <p style="color: white">Your secret information is RUCTF_29793ced32a8c89481c83827cf24647a</p> </body> </html>
Flag is RUCTF_29793ced32a8c89481c83827cf24647a.