Network encryption cracking

Network encryption cracking is the breaching of network encrptions (eg WEP, WPA, ...), usually trough the use of a special encryption cracking software. It may be done trough a range of attacks (active and passive) including injecting traffic, decrypting traffic and dictonary-based attacks.

Methods

As mentioned above, several types of attacks are possible. More precisely they are:

• Decrypting traffic based on tricking access points (active attack)
• Injecting traffic based on known plaintext (active attack)
• Gathering traffic and performing brute force/dictionary based attacks
• Decrypting traffic using statistical analysis (passive attack)

Injecting traffic

Injecting traffic means inserting forged encrypted messages into the network. It may be done if either the key is known (to generate new messages), but also if the key is not known and only a encrypted message and plaintext message is gathered, trough comparisation of the two. Programs able to do the latter are Aireplay and WepWedgie.

Decrypting

Decryption often requires 2 tools; 1 for gathering packets and another for analysing the packet and determining the key. Gathering packets may be done trough tools as WireShark, Prismdump, ... and cracking may be done trough tools as WEPCrack, AirSnort, AirCrack, WEPLab, ...

When gathering packets, often a great amount of them are required to perform cracking. Depending on the attack used, 5-16 million frames may be required. The attack-command itself however is surprisingly simple. Some examples:

Wepcrack

will be added in couple hours .... ;)

Comparisation of tools

A comparisation of the tools noted above may be found at Security Focus.