how can I set the mask to a md5 hash result of itself?

how can I set the mask to a md5 hash result of itself? - Printable Version

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how can I set the mask to a md5 hash result of itself? - yuzo555 - 03-31-2018

md5(abcd[salt])=0efa706032b161be6802d5ae093a97cd
what we know is the [salt] consists of 32 characters ( 0123456789abcdef ), seems like a md5 hash.
now I want crack this salt,
if I try to do this:

Code:
hashcat64 md5_hash.txt -m 0 -a 3 abcd?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h?h

I think it's impossible.

Sometime the [salt] was created by md5(a simple str),
in fact, in this case, the [salt] is md5(simple) = 8dbdda48fb8748d6746f1965824e966a

So, my question is, how can I set the mask to a md5 hash result of itself?
suck as...
hashcat64 md5_hash.txt -m 0 -a 3 abcd[md5(?s?s?s?s?s?s)]

RE: how can I set the mask to a md5 hash result of itself? - undeath - 03-31-2018

hex encoded or binary? not that it really matters because the search space is too large anyway.

RE: how can I set the mask to a md5 hash result of itself? - yuzo555 - 04-01-2018

I mean, if the 32 bytes salt is just a md5 hash of some simple text, and I search it as a 32 bytes completely random value,
that's too stupid.

So if I already knew the salt is a md5 hash of some short text, can I figure out the short text?

RE: how can I set the mask to a md5 hash result of itself? - undeath - 04-01-2018

Basically your salt is the "password" you are looking for. There should be a corresponding hash mode.

RE: how can I set the mask to a md5 hash result of itself? - yuzo555 - 04-01-2018

I got it, but another problem.
In my practical case, "Salt-length exception"
... why there is a limit to salt string.. I don't get it.

My salt length is 65..

RE: how can I set the mask to a md5 hash result of itself? - philsmd - 04-01-2018

You are using the wrong hash mode. You need to use this one:
-m 3710 = md5($salt.md5($pass))

(Note: if you know the original password and are looking for the salt, you need to switch the role of these two and therefore the salt becomes your password which you are trying to find out and the original pass is known and therefore could be seen as your salt)

See https://hashcat.net/wiki/doku.php?id=example_hashes

The hash format is like this:

Code:
hash:salt

in your case it is:

Code:
hash:abcd

and your password candidate list should contain the correct password whoes MD5 digest is 8dbxxxx8fb8748dxxxxf1965xxxxe966a (i.e. in this case "simple", without quotes)