mask attack with a max occurrence

mask attack with a max occurrence - Printable Version

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mask attack with a max occurrence - lloydXmas - 08-03-2017

I'd like to run a mask attack wherein I know the length of a given password and also that there will be no more than 2 occurrences of a specific charset (i.e. certain symbols). What util or type of attack would help me limit the occurrence symbols in a mask attack? Thanks for any tips.

RE: mask attack with a max occurrence - philsmd - 08-03-2017

maskprocessor (https://github.com/hashcat/maskprocessor) has 2 options:
-q, --seq-max=NUM Maximum number of multiple sequential characters
-r, --occurrence-max=NUM Maximum number of occurrence of a character

(-q filters out all password candidates that have *more or equal* characters than the value specified directly next to each other, -r instead checks if the password candidate does not have more or equal identical characters within the *whole* password candidate/line)

You could simply pipe the output of maskprocessor to hashcat, e.g.

Code:
mp64 -q 3 ?a?a?a?a?a | hashcat -m 0 -a 0 -w 4 hash.txt

RE: mask attack with a max occurrence - lloydXmas - 08-04-2017

Thanks for your help. Can the maskprocessor limit the occurrence of a defined set of characters though? So let’s say I want to define a charset as such:

Code:
--custom-charset1=%#=+

And I want to generate all possibilities that contain none, one, or two occurrences of any character from that charset.
So for instance, these would be valid possibilities:

Code:
bnkrwcvt

bnk#wcvb

bnk#wcv%

bnk#wcv#

bnk++wcv

While the following would be an invalid possibility (as it contains three occurrences of charset1):

Code:
bnk#w+v%

Can I specify which characters I want to use with the --occurrence-max option?