Attacking VPN's

1. VPN penetration testing
By
Abdul Adil

2. Who am i?
• Web application & Network pentester
• Malware reverse engineering
• Regular to Null Hyderabad chapter
• Email: Abdul.Adil@connectica.in
• Website: Connectica.in
• Twitter:@AbdulAdil02

3. Agenda
• What & Why VPN?
• Types of VPN
• VPN Internals
• VPN issues
• Demo
• Questionnaire?

4. What & Why VPN?
• VPN stands for “Virtual private network”.
• It extends a private network across a public network (internet).
• It establishes a virtual point-to-point connection.
• Connection is encrypted!.

5. Scenario of VPN usage

6. Type of VPN protocol
• PPTP
• IPSec
• SSL VPN
• Hybrid VPN

7. Types of VPN protocol
• PPTP(Point to point tunneling protocol): This is the most common and widely used
VPN protocol. They enable authorized remote users to connect to the VPN network
using their existing Internet connection and then log on to the VPN using password
authentication.
• IPSec: Trusted protocol which sets up a tunnel from the remote site into your central
site. As the name suggests, it’s designed for IP traffic. IPSec requires expensive, time
consuming client installations and this can be considered an important
disadvantage.

8. VPN protocol & types
•SSL VPN:SSL or Secure Socket Layer is a VPN accessible via https over web
browser. SSL creates a secure session from your PC browser to the
application server you’re accessing. The major advantage of SSL is that it
doesn’t need any software installed because it uses the web browser as the
client application.
•Hybrid VPN: It combines the features of SSL and IPSec & also other types
of VPN types. Hybrid VPN servers are able to accept connections from
multiple types of VPN clients. They offer higher flexibility at both client and
server levels and bound to be expensive.

9. VPN Internals

10. VPN Traffic

11. VPN appliance and applications
VPN Appliance
VPN application

12. VPN issues
• Some of the protocols provide weak encryptions.
• Vulnerable to brute force attacks as there is only one DES 56bit key to
crack.
• RC4 cipher which is used for encryption does not doesn’t helps us
with the integrity of the data.
• If not configure properly it can lead to leakage of data over
network(Port fail vulnerability).

14. Twitter:@AbdulAdil02 Email:Abdul.Adil@connectica.in

15. Thanks to Null Hyderabad.