How to Hack a WPA Wireless Network (Wifi) using Aircrack-ng and John the Ripper

Here is a video tutorial I created showing how easy it is to hack a wireless network using WPA keys for their security. It's a short 12 minute video and I hope you find it not only instructional, but also liberating. After all, informed people make the best decisions.

John the Ripper (JtR) cracks passwords offline. That is, "incorrect number of passwords entered limit" does not affect  JtR. As you can see in the video, using aireplay-ng, fake deauthentication packets were injected to the wireless access point  to force all users to reauthenticate (without them knowing it). During reauthentication, the WPA keys are exchanged between the client and the wireless access point. This exchange was recorded into a file "wificrack.cap" and the hashed PSK (Pre-Shared Key) was then cracked using JtR.  In the video, you can also see that the output file of airodump-ng can be opened using Wireshark. Opening the cap file with Wireshark reveals a lot of information about the clients connected to the wireless access point. For instance, we know the wireless AP is a Cisco-Li (Cisco-Linksys), and the WPA handshake captured was from an Apple device. The MAC address is even shown!

How to Access Skype Chat History of Another Person or PC.

Internet messengers (IM) indeed made the world smaller, and skype is undoubtedly the major contributor to this phenomena. 

Skype is simple to use, and hard to block. With skype, you can do free calls and videoconferencing; share your desktop; and, share files such as documents and photos with any other skype users anywhere. Skype has the ability to use any available open port to communicate to the internet which made it a bane for traditional port-based firewalls to block (a headache for most network engineers).

But is skype safe? 

Practical SSH Tunneling: Using Putty to Bypass Web Filters and Firewalls

About SSH v.2 and SSH tunneling

SSH (Secure Shell) was an Internet Task Force (IETF) protocol for encrypting traffic to access a remote host. SSH v2 standard came out in 2006 and is incompatible with SSH v.1.  Version 2 uses Diffie-Hellman (DH) key exchanges to create a tunnel between a client and a server. Thus, SSH works very similary like a VPN and was, in fact, called a poor man's VPN. SSH has lower levels of security and encryption than VPN. Apart from that, I don't really know the exact difference between an SSH tunnel and a VPN and if you happen to do, please feel free to post a comment or link to your blog/article that explains SSH versus VPN.

SSH v.2 is both a boon and a bane for network engineers. I've been using SSH v.2 to do a myriad of things, some of which to purposely circumvent network policies that would normally disallow people to access other parts of the network. For this article, we will use SSH tunneling to bypass corporate firewall and webfiltering. This is possible using any Web Socket capable browser such as Mozilla Firefox and Opera (I've heard  Google Chrome will support it soon).