for this available: $wpapcap2john wpa.cap > crackme $./john -w:password.lst -fo=wpapsk-cuda crackme Results Successful password cracking via piping these into aircrack-ng: Opening sampleorg_airodump-01.cap Reading packets, please wait... Aircrack-ng 1.1 [00:00:05] 9123 keys tested (1876.54 k/s) KEY FOUND! [ sample2012 ] Master Key : 2A 7C B1 92 C4 61 A9 F6 7F 98 6B C1 AB 53 7A 0F 3C AF D7 9A 0C BD F0 4B A2 44 EE 5B 13 94 12 12 Transient Key : A9 C8 AD 47 F9 71 2A C6 55 F8 F0 73 FB 9A E6 1D 23 D9 31 25 5D B1 CF EA 99 2C B3 D7 E5 7F 91 2D 56 25 D5 9A 1F AD C5 02 E3 2C C9 ED 74 55 BA 94 D6 F5 0A D1 3B FB 39 40 19 C9 BA 65 2E 49 3D 14 EAPOL HMAC : F1 DF 09 C4 5A 96 0B AD 83 DD F9 07 4E FA 19 74 The fourth line of the above output provides some useful information about the effectiveness of a strong WPA key. That rate of approximately 2000 keys per second means that a full-on, brute-force attack against a similar-length key that was truly random (and therefore immune to dictionary-based attacks) would take about 70^9 or 20 trillion seconds, which is well over 600,000 years. Or, for those who favor length and simplicity over brevity and complexity, a key containing four words chosen from among the 10,000 most common English dictionary words would still take approximately 150,000 years to crack (using this method on an average laptop). It is worth noting that an attacker with the resources and the expertise could increase this rate by a factor of a hundred. Using a computer with powerful graphical processing units (GPUs) or a cloud computing service like Amazon’s EC2, it is possible to test 250,000 or more keys per second. A setup like this would still take several lifetimes to guess a strong password, however. Regardless, the success of this attack against a wireless network would allow an attacker to bypass all perimeter controls, including the network firewall. Without access to the office LAN, a non-ISP, non-government attacker would have to position himself on the same network as an external staff member in order to exploit any flaws in the organization’s email or file-sharing services. With access to the local network, however, that attacker could begin carrying out Local attacks quite quickly, and from a distance. Page 49 of 240