Creating wordlists with crunch v3.0
CRUNCH v3.0
Warning... this is a looong post, grab a beverage.. ;) Also heavy on images..
PRE-INTRO
Since the post on Creating wordlists with crunch v2.4 made in April last year, crunch has gone through
quite a few changes and improvements and bofh28 has now released v3.0 ! (on 16-05-2011)
To make sure that the information on this blog is staying upto date, its time for a new and improved post.
There will be a lot of duplication from my previous post on crunch, but it should then at least
be a more or less full and complete post.
I have tried to follow the alphabetical order of the options and have done a chapter per option/switch.
Please leave comments should the post be lacking information on anything you feel should be included.
INTRODUCTION
crunch is a tool for creating bruteforce wordlists which can be used to audit password strength.
The size of these wordlists is not to be underestimated, however crunch can make use of patterns to reduce wordlist sizes, can compress output files in various formats and (since v2.6) now includes a message advising the size of the wordlist that will be created, giving you a 3 second window to stop the creation should the size be too large for your intended use.
The full range of options is as follows ;
-b Maximum bytes to write per file, so using this option the wordlist to be created can be split into various
sizes such as KB / MB / GB (must be used in combination with "-o START" switch)
-c Number of lines to write to output file, must be used together with "-o START"
-d Limits the number of consecutive identical characters ( crunch v3.2)
-e Specifies when crunch should stop early ( crunch v3.1)
-f Path to the charset.lst file to use, standard location is '/pentest/passwords/crunch/charset.lst
to be used in conjunction with the name of the desired charset list, such as 'mixalpha-numeric-space'
-i Inverts the output sequence from left-to-right to right-to-left
(So instead of aaa, aab, aac, aad etc, output would be aaa baa caa daa)
-l When specifying custom patterns with the -t option, the -l switch allows you to identify which of the characters
should be taken as a literal character instead of a place holder ( @,%^ )
-o Allows you to specify the file name / location for the output, e.g. /media/flashdrive/wordlist.txt
-p Prints permutations of the words or characters provided in the command line.
-q Prints permutation of the words or characters found in a specified file
-r Resumes from a previous session, exact same syntax to be used followed by -r
-s Allows you to specify the starting string for your wordlist.
-t Allows you to specify a specific pattern to use. Probably one of the most important functions !
Place holders for fixed character sets are ;
@ -- lower case alpha characters
, -- upper case alhpa characters
% -- numeric characters
^ -- special characters (including space)
-u Supresses the output of wordlist size & linecount prior starting wordlist generation.
-z Adds support to compress the generation output, supports gzip, bzip & lzma
All the below is done on backtrack 5, only tested on the 32bit versions.
crunch is not installed by default on BT5 and as yet (22-05-2011) not yet in the repo's.
(When it does hit the repo's I will amend this post to reflect installing from repo's)
so download from the source at ;
http://sourceforge.net/projects/crunch-wordlist/
