aircrack is a 802.11 WEP key cracker. It implements the so-called Fluhrer - Mantin - Shamir (FMS) attack, along with some new attacks by a talented hacker named KoreK. When enough encrypted packets have been gathered, aircrack can almost instantly recover the WEP key.-aircrack is a 802.11 WEP key cracker. It implements the so-called Fluhrer- Mantin- Shamir (FMS) attack, along with some new attacks by a talented hacker named KoreK. When enough encrypted packets have been gathered, aircrack can almost instantly recover the WEP key.