We have already learned about the dictionary attacks in the previous section. During a particular engagement with an organization we may identify a certain pattern that is used for all the passwords. So, we may want to have a word-list inline with a particular pattern. Password profiling helps us generate word-lists aligned with the specific pattern.

Kali Linux has a tool called crunch which helps us generate word-lists using custom patterns.

crunch 3 5 0123456789abcdefghijklmnopqrstuvwxyz

The preceding syntax will generate a word-list with words of minimum length 3, maximum length 5, and containing all possible permutations and combinations from the character-set 0123456789abcedefghijklmnopqrstuvwxyz. For further help, we can refer to crunch help using man crunch command, as shown in the following image: