AirSnort

AirSnort is a Linux and Microsoft Windows utility (using GTK+) for decrypting WEP encryption on an 802.11b network. Distributed under the GNU General Public License, AirSnort is free software.

Scott Fluhrer, Itsik Mantin and Adi Shamir (who was one of the inventors of the RSA encryption algorithm) released a paper entitled Weaknesses in the Key Scheduling Algorithm of RC4. In August 2001, based on the security flaws described therein, Blake Hegerle and Jeremy Bruestle made public a tool that must gather roughly five to ten million encrypted packets from a wireless access point before it can attempt to recover the wireless key. Depending on the environment, this can take as little as a few minutes or more commonly a few hours and possibly a few days.

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