We left off at sniffing the packets, but unless you can spare a whole week if trying to get access to a mostly inactive network, we’re going to need to generate some sort of traffic to speed things up. To do this, we are going to take advantage of packet injection, and only then we’ll see that Data counter jump up to a useable level. Let’s open another terminal, and run the command: ...
This is where it gets fun. In this part, we’ll set our wireless interface to monitor mode, and we’ll start sniffing some packets and dumping the captures into a file for further analysis. To start, we have to list the available wireless interfaces to the system. Hopefully your card is compatible and has a driver already loaded. Let’s fire up Konsole (a terminal application), which is the third icon from the bottom-left, and we’ll type: ...
It’s been long known that WEP is a very insecure wireless encryption protocol, and this is due to weak Initialization Vectors (IV) being used within. See, the engineers that designed the WEP protocol attempted to create a stronger encryption by adding a 24 bit IV to the cypher key that changes constantly, thus “eliminates” the repeated encryption of data with the same key over an over. The problem is, these IV’s are too short, and are periodically reused… which means that if we can sniff enough data over the air, and get the AP to reuse IV’s eventually, we can figure out the key. ...