intercept data from VPN over unencrypted L2TP

[sevdalin.abadzhiev-lewin 1]

Hello all,

 

i have a question about vpn and especialy L2TP without encryption. Assuming that we have such L2TP VPN tunnel between two network devices. The one is the client and another the server. How would be the traffic 

intercept? When we assuming that the hacker has not physically access neither to the server nor to the client. It would be also difficult to do man in the middle from internet, because the hacker has not access to ISP devices.

To hacking a client in an network behind the client router which is creating the tunnel and to make man in the middle is also not very good idea, because  the admins can notice a low perfromance.

Thanks in advanced!

greetings

Sev

[herman 48]

I am not sure I follow your logic. To intercept traffic you need to be in path (or middle) to capture or redirect traffic. 

So if an attacker can't do that he will go after either the client or server end to exploit a public available vector such as: malware over e-mail or social media for the client or exposed daemons on the server (web, database, snmp, etc.). Of special interest are the routers on either side as many IoT/Embedded stuff is usually pretty easy to break.