With AIRDECAP-NG you can decrypt WEP/WPA/WPA2 capture files. As well, it can also be used to strip the wireless headers from an unencrypted wireless capture. it outputs a new file ending with “-dec.cap” which is the decrypted/stripped version of the input file.
airdecap-ng [options] <pcap file>
Common options: -l : don't remove the 802.11 header -b <bssid> : access point MAC address filter -e <essid> : target network SSID WEP specific option: -w <key> : target network WEP key in hex WPA specific options: -p <pass> : target network WPA passphrase -k <pmk> : WPA Pairwise Master Key in hex --help : Displays this usage screen
Decrypting WPA2 catured packtes :
cyborg@cyborg:~$ airdecap-ng -e tempztrela -p trendztrela packetscap-02.cap Total number of packets read 88673 Total number of WEP data packets 0 Total number of WPA data packets 345 Number of plaintext data packets 0 Number of decrypted WEP packets 0 Number of corrupted WEP packets 0 Number of decrypted WPA packets 117