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Date: Wed, 20 May 2015 02:12:33 +0200
From: magnum <john.magnum@...hmail.com>
To: john-users@...ts.openwall.com
Subject: Re: Advise on best approach (truecrypt pw based on pdf
 file)

The hash_nopart one from sdb has entries with mostly nulls so is not 
likely correct. I just made some quick tests and reviewed the code. 
Unfortunately, truecrypt_volume2john doesn't recognize any signature or 
magic, so you can feed it ANY data and as long as it's at least 512 
bytes it will happily produce six different hashes: One for each of the 
three algorithms, plus another set of three for possible hidden volumes. 
I believe there's no way to make it any better - truecrypt is designed 
to be plausably deniable. Of the six ones always produced, I believe 
only one is ever correct (if any) and often you won't know which.

I tried running truecrypt_volume2john on some actual truecrypt container 
(file) I had lying around. Obviously it "found" six hashes in it too. 
When trying with the correct password, the correct one was cracked 
(apparently it was a RIPEMD_160 one) while the other ones are bogus 
random data that can't ever be cracked.

So, if last weeks attempts were made using the file from sbd1, and 
without using the --format option no narrow down to a particular algo, I 
think you did correct. If you did narrow it down to eg. 
--format=tc_ripemd160, I hope that's because you KNOW that is the algo used.

magnum


On 2015-05-19 23:23, Demian Smith wrote:
> Not all hope is lost, so?
>
> So, what I did was:
>
> attach the external device to usb and verify it's "path" via lsblk
> and/or truecryp. This led to
> sdb                    8:16   0 465.7G  0 disk
> └─sdb1             8:17   0 465.7G  0 part
>
> I than do:
> [demian@...nymous:~/.bin/JtR/run]$ ./truecrypt_volume2john /dev/sdb1 >
> ~/hash
>
> which results in the attached hash file.
>
> I had tried the same on a usb key, as well running truecrypt2john versus
> the partition on sdb1, which then had been "cracked"...
>
> If I create a hashfile on /dev/sdb instead, I get
>
> john --session=wl --wordlist=/home/wpd_for_mark_second.txt ~/no_partition
> ASCII -> ASCII -> ASCII
> Warning: detected hash type "tc_aes_xts", but the string is also
> recognized as "tc_ripemd160"
> Use the "--format=tc_ripemd160" option to force loading these as that
> type instead
> Loaded 6 password hashes with 6 different salts (tc_aes_xts, TrueCrypt
> AES256_XTS [SHA512 128/128 SSE4.1 2x /RIPEMD160/WHIRLPOOL])
> Loaded hashes with cost 1 (hash algorithm [1:SHA512 2:RIPEMD160
> 3:Whirlpool]) varying from 1 to 3
> Will run 4 OpenMP threads
>
> If I force ripemd w/ --format=tc_ripemd160:
> initUnicode(UNICODE,ASCII/ASCII)
>
>
> ASCII->ASCII->ASCII
>
>
> Loaded 2 password hashes with 2 different salts (tc_ripemd160, TrueCrypt
> AES256_XTS [RIPEMD160 32/64])
>
> Will run 4 OpenMP threads
>
> while the hashfile itself looks different ...
>
> i did look into the doc folder but could not spot anything related to
> truecrypt, I hope I did not just miss it...
>
> Also, I hope I just made a mistake somewhere on the lines of generating
> the hashes, maybe ...
>
> Thanks for keeping my hopes up,
> D
> --
> 'It's no measure of mental health to be well adjusted
> to a profoundly sick society.'
>
> Sinéad O'Connor
>
>   ★ On 15/05/19 09:00 p.m. Magnum wrote ★
>> On 2015-05-19 20:35, Demian Smith wrote:
>>> I right now run the two filters on the first txt file I create from the
>>> suspect pdf and will then go back to incremental, as the Markov mode -
>>> in my case - does not appear to be producing useful candidates.
>>>
>>> Thanks again for all the effort, I'm pretty sure this is a layer 8 issue
>>> right now :s
>>
>> Maybe we should revert to verifying your truerypt_volume2john
>> invocation/results.
>>
>> Please recap what you had, what you did and what you got. Were you
>> feeding truecrypt_volume2john a file or a device special node? Was there
>> any output on stderr? How does your "hash" file look? I still wonder why
>> you got two "hashes".
>>
>> magnum
>>
>>


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