John The Ripper Crack Sha512 Encryption

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Viewed 8k times 2 I've been playing with John The Ripper (JtR) to try to crack/audit a salted password that was hashed with SHA-512, with 20 interactions according to the source (for the curious, this is a Rails app, with the authlogic gem). If I understood things correctly, JtR expects its hashes in a file, where each hash follows certain format. And of course I have extended version of John the Ripper that support raw-md5 format. It turned out that John doesn't support capital letters in hash value! They have to be written in small letters like this.

I just spent at least 15 minutes trying to figure out why every single post on the Internet tells me to place MD5 hash in a file and call John like this
john --format=raw-md5 --wordlist=/usr/share/dict/words md5.txt
and yet, it constantly gives me an error message:
No password hashes loaded (see FAQ)
The content of md5.txt was:
20E11C279CE49BCC51EDC8041B8FAAAA
I even tried prepending dummy user before this hash, like this:
dummyuser: 20E11C279CE49BCC51EDC8041B8FAAAA
but without any luck.
And of course I have extended version of John the Ripper that support raw-md5 format.
It turned out that John doesn't support capital letters in hash value! They have to be written in small letters like this:
20e11c279ce49bcc51edc8041b8fbbb6
after that change, everything worked like a charm. What a stupid error!?After seeing how to compile John the Ripper to use all your computer's processors now we can use it for some tasks that may be useful to digital forensic investigators: getting around passwords. Today we will focus on cracking passwords for ZIP and RAR archive files. Luckily, the JtR community has done most of the hard work for us. For this to work you need to have built the community version of John the Ripper since it has extra utilities for ZIP and RAR files.
For this exercise I have created password protected RAR and ZIP files, that each contain two files.
The password for the rar file is 'test1234' and the password for the zip file is 'test4321'.

John The Ripper Crack Sha512 Encryption Software

In the 'run' folder of John the Ripper community version (I am using John-1.7.9-jumbo-7), there are two programs called 'zip2john' and 'rar2john'. Run them against their respective file types to extract the password hashes:
This will give you files that contain the password hashes to be cracked... something like this:
After, that you can run John the Ripper directly on the password hash files:

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You should get a message like: Loaded 1 password hash (PKZIP [32/64]). By using John with no options it will use its default order of cracking modes. See the examples page for more information on modes.
Notice, in this case we are not using explicit dictionaries. You could potentially speed the cracking process up if you have an idea what the password may be. If you look at your processor usage, if only one is maxed out, then you did not enable OpenMP when building. If you have a multi-processor system, it will greatly speed up the cracking process.
Now sit back and wait for the cracking to finish. On a 64bit quad-core i7 system, without using GPU, and while doing some other CPU-intensive tasks, the password was cracked in 6.5 hours.
Sha512

John The Ripper Crack Sha512 Encryption Tool

Now if you want to see the cracked passwords give john the following arguments:
It should output something like:

John The Ripper Crack Sha512 Encryption Download

Note: the hash file should have the same type of hashes. For example, we cannot put the rar AND zip hashes in the same file. But this means you could try to crack more than one zip/rar file at a time.
For the rar file it did not take nearly as long since the password was relatively common. If you take a look at john.conf in the run directory, it has a list of the patterns it checks (in order). The pattern 12345 is much more likely than 54321, so it is checked first resulting in a quick crack.

John The Ripper Crack Sha512 Encryption Key