From the aircrack-ng site.....
http://aircrack-ng.org/doku.php?id=aircrack-ng
Next, we look at cracking WEP with a dictionary. In order to do this, we need dictionary files with ascii or hexadecimal keys to try. Remember, a single file can only have ascii or hexadecimal keys in it, not both.
WEP keys can be entered in hexadecimal or ascii. The following table describes how many characters of each type is required in your files.
WEP key length
in bits Hexadecimal
Characters Ascii
Characters 64105 1282613 1523216 2565829 Example 64 bit ascii key: “ABCDE”
Example 64 bit hexadecimal key: “12:34:56:78:90” (Note the ”:” between each two characters.)
Example 128 bit ascii key: “ABCDEABCDEABC”
Example 128 bit hexadecimal key: “12:34:56:78:90:12:34:56:78:90:12:34:56”
To WEP dictionary crack a 64 bit key:
aircrack-ng -w h:hex.txt,ascii.txt -a 1 -n 64 -e teddy wep10-01.cap
Where:
- -w h:hex.txt,ascii.txt is the list of files to use. For files containing hexadecimal values, you must put a “h:” in front of the file name.
- -a 1 says that it is WEP
- -n 64 says it is 64 bits. Change this to the key length that matches your dictionary files.
- -e teddy is to optionally select the access point. Your could also use the ”-b” option to select based on MAC address
- wep10-01.cap is the name of the file containing the data. It can be the full packet or an IVs only file. It must contain be a minimum of four IVs.
Here is a sample of the output:
Aircrack-ng 0.7 r247
[00:00:00] Tested 2 keys (got 13 IVs)
KB depth byte(vote)
0 0/ 0 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0)
1 0/ 0 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0)
2 0/ 0 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0)
3 0/ 0 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0)
4 0/ 0 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0) 00( 0)
KEY FOUND! [ 12:34:56:78:90 ]
Probability: 100%