Security Basics: Re: Fwd: How does the Cain and Abel SAM dump works?

["Dave Hull" <dphull () trustedsignal com>]

On Tue, Jul 15, 2008 at 2:14 PM, Eric Snyder <Eric.S () aefcu com> wrote:
> How are you checking / cracking longer, 15 character plus, passwords?
> The best table I have seen is 14 character.  Do you have a source for
> 15+ character tables that use every possible printable characters;
> commas, spaces, grave accents, etc.?
Remember that if the password is more than 14 characters, Windows
won't write an LM hash of it to the SAM file. Instead, an NT hash will
be written along with a bogus LM hash. The LM hash is pretty weak as
it is hashed on a seven bit boundary, thus your Rainbow tables
actually only have to have hashes computed for seven character
strings.

This is why I recommend passwords be at least 15 characters. In my
opinion, size matters more than complexity.

-- 
Dave Hull
CISSP, GCFA, GCIH, GREM, SSP-MPA, CHFI
Trusted Signal, LLC
http://trustedsignal.com

SANS Mentor Security 508: Computer Forensics, Investigation and Response
https://www.sans.org/mentor/details.php?nid=11673