Re: How Windows Password Cracking Programs Work

Hi all,

these programs in most cases calculate (or there are some tools which
pre-calculate) hashes from text passwords and compare it with hash of
the passwords.
2 very similar passwords have completely different hashes, i.e.
password - 286755fad04869ca523320acce0dc6a4
passwords - 6f59c8e9229e384c2935e75075825566

(md5 algorithm used in previous example.)

The output of hash algorithms is all the time the same length.
For all hash functions its mathematically impossible (we hope :)) to
derive the original text password from encrypted hash.
But it can be that 2 different passwords have the same hash. Its
called "collision".
Regards, Michal


On 22 Jul 2006 15:33:12 -0000, winshel@xxxxxxxxxxxxxxxxxx
<winshel@xxxxxxxxxxxxxxxxxx> wrote:
Please excuse my lack of technical understanding of windows password cracking software.


My question is whether windows password cracking programs has to do with how these programs work.


Is it correct that they do not crack a password one character at a time? That is, the password cracking programs aren't able to determine that they have cracked the first character, or the first two or first three characters?


Also, is it correct that password cracking programs aren't able to determine - ahead of time - how long a windows password is?


Thanks.



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