Crunch Wordlist generator is a tool which comes by default with Kali Linux. It can create a wordlist based on criteria you specify. The output from crunch can be sent to the screen, file, or to another program. The required parameters are:
min-len
The minimum length string you want crunch to start at. This option is required even for parameters that won’t use the value.
max-len
The maximum length string you want crunch to end at. This option is required even for parameters that won’t use the value.
charset string
You may specify character sets for crunch to use on the command line or if you leave it blank crunch will use the default character sets. The order MUST BE lower case characters, upper case characters, numbers, and then symbols. If you don’t follow this order you will not get the results you want. You MUST specify either values for the character type or a plus sign. NOTE: If you want to include the space character in your character set you must escape it using the \ character or enclose your character set in quotes i.e. “abc “. See the examples 3, 11, 12, and 13 for examples.
OPTIONS (CRUNCH WORDLIST GENERATOR)
-b number[type]
Specifies the size of the output file, only works if -o START is used, i.e.: 60MB The output files will be in the format of starting letter-ending letter for example: ./crunch 4 5 -b 20mib -o START will generate 4 files: aaaa-gvfed.txt, gvfee-ombqy.txt, ombqz-wcydt.txt, wcydu-zzzzz.txt valid values for type are kb, mb, gb, kib, mib, and gib. The first three types are based on 1000 while the last three types are based on 1024. NOTE There is no space between the number and type. For example 500mb is correct 500 mb is NOT correct.
-c number
Specifies the number of lines to write to output file, only works if -o START is used, i.e.: 60 The output files will be in the format of starting letter-ending letter for example: ./crunch 1 1 -f /pentest/password/crunch/charset.lst mixalpha-numeric-all-space -o START -c 60 will result in 2 files: a-7.txt and 8-\ .txt The reason for the slash in the second filename is the ending character is space and ls has to escape it to print it. Yes you will need to put in the \ when specifying the filename because the last character is a space.
-d numbersymbol
Limits the number of duplicate characters. -d 2@ limits the lower case alphabet to output like aab and aac. aaa would not be generated as that is 3 consecutive letters of a. The format is number then symbol where number is the maximum number of consecutive characters and symbol is the symbol of the the character set you want to limit i.e. @,%^ See examples 17-19.
-e string
Specifies when crunch should stop early
-f
/path/to/charset.lst charset-name
Specifies a character set from the charset.lst
-i
Inverts the output so instead of aaa,aab,aac,aad, etc you get aaa,baa,caa,daa,aba,bba, etc
-l
When you use the -t option this option tells crunch which symbols should be treated as literals. This will allow you to use the placeholders as letters in the pattern. The -l option should be the
same length as the -t option. See example 15.
-m
Merged with -p. Please use -p instead.
-o wordlist.txt
Specifies the file to write the output to, eg: wordlist.txt
-p
charset OR -p word1 word2 …
Tells crunch to generate words that don’t have repeating characters. By default crunch will generate a wordlist size of #of_chars_in_charset ^ max_length. This option will instead generate
#of_chars_in_charset!. The ! stands for factorial. For example say the charset is abc and max length is 4.. Crunch will by default generate 3^4 = 81 words. This option will instead generate 3!
= 3x2x1 = 6 words (abc, acb, bac, bca, cab, cba). THIS MUST BE THE LAST OPTION! This option CANNOT be used with -s and it ignores min and max length however you must still specify two numbers.
-q filename.txt
Tells crunch to read filename.txt and permute what is read. This is like the -p option except it gets the input from filename.txt.
-r
Tells crunch to resume generate words from where it left off. -r only works if you use -o. You must use the same command as the original command used to generate the words. The only exception to this is the -s option. If your original command used the -s option you MUST remove it before you resume the session. Just add -r to the end of the original command.
-s
startblock specifies a starting string, eg: 03god22fs
-t @,%^
Specifies a pattern, eg: @@god@@@@ where the only the @’s, ,’s, %’s, and ^’s will change.
@ will insert lower case characters
, will insert upper case characters
% will insert numbers
^ will insert symbols
-u
The -u option disables the print percentage thread. This should be the last option.
-z gzip, bzip2, lzma, and 7z
With this option, Crunch Wordlist generator compresses the output from the -o option. Valid parameters are gzip, bzip2, lzma, and 7z.
gzip is the fastest but the compression is minimal. bzip2 is a little slower than gzip but has better compression. 7z is slowest but has the best compression.
EXAMPLES (CRUNCH WORDLIST GENERATOR)
Example 1
crunch 1 8
crunch will display a wordlist that starts at a and ends at zzzzzzzz
Example 2
crunch 1 6 abcdefg
crunch will display a wordlist using the character set abcdefg that starts at a and ends at gggggg
Example 3
crunch 1 6 abcdefg\
there is a space at the end of the character string. In order for crunch to use the space you will need to escape it using the \ character. In this example you could also put quotes around the letters
and not need the \, i.e. “abcdefg “. Crunch will display a wordlist using the character set abcdefg that starts at a and ends at (6 spaces)
Example 4
crunch 1 8 -f charset.lst mixalpha-numeric-all-space -o wordlist.txt
crunch will use the mixalpha-numeric-all-space character set from charset.lst and will write the wordlist to a file named wordlist.txt. The file will start with a and end with ” ”
Example 5
crunch 8 8 -f charset.lst mixalpha-numeric-all-space -o wordlist.txt -t @@dog@@@ -s cbdogaaa
crunch should generate a 8 character wordlist using the mixalpha-number-all-space character set from charset.lst and will write the wordlist to a file named wordlist.txt. The file will start at cbdogaaa and end at ” dog ”
Example 6
crunch 2 3 -f charset.lst ualpha -s BB
crunch with start generating a wordlist at BB and end with ZZZ. This is useful if you have to stop generating a wordlist in the middle. Just do a tail wordlist.txt and set the -s parameter to the next
word in the sequence. Be sure to rename the original wordlist BEFORE you begin as crunch will overwrite the existing wordlist.
Example 7
crunch 4 5 -p abc
The numbers aren’t processed but are needed.
crunch will generate abc, acb, bac, bca, cab, cba.
Example 8
crunch 4 5 -p dog cat bird
The numbers aren’t processed but are needed.
crunch will generate birdcatdog, birddogcat, catbirddog, catdogbird, dogbirdcat, dogcatbird.
NOTES
- Starting in version 2.6 Crunch Wordlist generator will display how much data is about to be generated. In 2.7 it will also display how many lines will be generated. Crunch will now wait 3 seconds BEFORE it begins generating data to give you time to press Ctrl-C to abort crunch if you find the values are too large for your application.
- I have added hex-lower (0123456789abcdef) and hex-upper (0123456789ABCDEF) to charset.lst.
- Several people have requested that I add support for the space character to crunch. crunch has always supported the space character on the command line and in the charset.lst. To add a space on the command line you must escape it using the / character. See example 3 for the syntax. You may need to escape other characters like ! or # depending on your operating system.
- Starting in 2.7 if you are generating a file then every 10 seconds you will receive the % done.
- Starting in Crunch Wordlist generator 3.0 I had to change the -t * character to a , as the * is a reserved character. You could still use it if you put a \ in front of the *. Yes it breaks crunch’s syntax and I do my best to avoid doing that, but in this instance it is easier to make the change for long term support.
- Some output is missing. A file didn’t get generated. The mostly explanation is you ran out of disk space. If you have verified you have plenty of disk space then the problem is most likely the filename begins with a period. In Linux filenames that begin with a period are hidden. To view them do a ls -l .*
- Crunch says The maximum and minimum length should be the same size as the pattern you specified, however the length is set correctly. This usually means your pattern contains a character that needs to be escaped. In bash you need to escape the followings: &, *, space, \, (, ), |, ‘, “, ;, <, >. The escape character in bash is a \. So a pattern that has a & and a * in it would look like this:
crunch 4 4 -t \&\*d@ An alternative to escaping characters is to wrap your string with quotes. For example:
crunch 4 4 -t “&*d@” If you want to use the ” in your pattern you will need to escape it like this: crunch 4 4 -t “&*\”@” - Please note that different terminals have different escape characters and probably have different characters that will need escaping. Please check the manpage of your terminal for the escape characters and characters that need escaping.
- When using the -z 7z option, 7z does not delete the original file. You will have to delete those files by hand in Crunch Wordlist generator