Aircrack is a Scripts software developed by Christophe Devine. After our trial and test, the software is proved to be official, secure and free. Here is the official description for Aircrack:

Aircrack-ng is an 802.11 WEP and WPA-PSK keys cracking program that can Recover Keys once enough data packets have been captured. It implements the standard FMS attack along with some optimizations like KoreK attacks, as well as the all-new PTW attack, thus making the attack much faster compared to other WEP cracking tools. In FACT, Aircrack-ng is a set of tools for auditing wireless networks.

If you are impatient and want to know how to get started, jump to the Getting Started Tutorial.

Aircrack-ng is the next generation of aircrack with lots of new features:

Better documentation (wiki, manpages) and support (Forum, trac, IRC: #aircrack-ng on Freenode).
More cards/drivers supported
More OS and platforms supported
New WEP attack: PTW
WEP dictionary attack
Fragmentation attack
Improved cracking speed
Capture with multiple cards
New tools: airtun-ng, packetforge-ng (improved arpforge), wesside-ng, easside-ng, airserv-ng, airolib-ng, airdriver-ng, airbase-ng, tkiptun-ng and airdecloak-ng
Optimizations, other improvements and bug fixing
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