Bypass VPN restriction

Sometimes ago, I discovered I can bypass VPN restriction using VM and WSL (Windows Subsystem for Linux). Certainly, it give me some kind of convenience to complete my work.

Everyone loves workaround

Have you ever do similar things ? For instance, you figure out how to workaround the security control to complete your sysadmin duty. Then, you make use of this technique every time when you need to complete a similar tasks.

In the past, I always did that when I was a sysadmin. I remember one time when I need to add a printer to a very restricted computer. The computer had no connection to domain controller, restricted add priner wizard GUI interface, limited GUI interface and limited executable files available. I was forced to explore every command related to add printer and understand every single step what add printer wizard do it for me. However, I was not not aware an attacker can exploit the same vulnerability. After many years, I read the SANS SEC660 book and took the GXPN exam. There is a section in the GXPN exam discussing about “Escaping Restricted Environments”. I realized that I use those advance technique since I was a sysadmin. It is awesome!

Security is about mindset and knowledge. You may not realize you need a security tool that you don’t know vulnerability exists.

Now, back to our bypass VPN restriction discussion, do not think routing all client traffic to VPN gateway with a security policy block all outgoing internet traffic can act as some kind of DLP solution. As you can see, suppose I should not be able to connect to internet after connecting to fortigate VPN, but in my VM!? 

Think outside the box, and you can always workaround it, and the hacker can also workaround it. Next time, do report your findings and never hide your secret sysadmin weapons!