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How to generate LM rainbow tables ?

PostPosted: Sun Nov 18, 2012 9:00 am
by pyr
Hi,

I would like to have GPU LM rainbow tables with charset upper+digit+specials, len 7 only.
How can I generate this ?
because I can't see LM in :
GRTGen-OpenCL.exe: missing option -h|--hashtype={NTLM, MD4, MD5, SHA1}

Thank you

Re: How to generate LM rainbow tables ?

PostPosted: Tue Nov 20, 2012 2:04 am
by Bitweasil
Right now, LM is not supported for the table tools at all. I suggest the freerainbowtables tools and tables for LM right now. It's on my list to add eventually, but is a very low priority given their tables.

Re: How to generate LM rainbow tables ?

PostPosted: Fri Nov 23, 2012 8:18 am
by frosty
You can brute force them with the Cryptohaze Multiforcer though, I think I clocked about 6 hours to go through all possible hashes with my GTX580.

Re: How to generate LM rainbow tables ?

PostPosted: Sat Nov 24, 2012 6:16 pm
by Bitweasil
frosty wrote:You can brute force them with the Cryptohaze Multiforcer though, I think I clocked about 6 hours to go through all possible hashes with my GTX580.


Depends on the charset.

If it's the US charset without lowercase, it's pretty quick.

If it's the full possible LM charset, it's a lot longer. But use the FRT tables then. :)

Re: How to generate LM rainbow tables ?

PostPosted: Mon Jan 07, 2013 10:47 am
by frosty
I used the tables from FRT and rcracki_mt, they work very well. One feature I really like is that if you know the LM and NTLM hashes for the same password, for example if you've used pwdump, then it uses the fast LM rainbow tables to find the uppercase password for the LM hash, and then uses that to reduce the keyspace and manually brute all combinations of upper/lower chars against the NTLM string.

That means you get the final password in its correct case, anything up to the 14 char limit of LM, but without the normally impossible time of running through length 14 on NTLM.

Bitweasil if you do ever support LM rainbow tables, I hope this is an added bonus :)