Openwall GNU/*/Linux - a small security-enhanced Linux distro for servers
[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Date: Tue, 18 Feb 2014 20:08:30 -0500
From: Rich Rumble <richrumble@...il.com>
To: john-users@...ts.openwall.com
Subject: Re: need to find a way to crack passwords with 16 to 20 length

On Tue, Feb 18, 2014 at 7:13 PM, Dan Tentler <dan@...nlabs.com> wrote:

> Company name, days of the week, phrases used around the office etc, all
> strung together, sometimes with symbols separating words, capitals, and
> numbers tossed on the end of the string.
> From a purely entropy standpoint it outwardly seems like it would be
> 'less work', but I haven't figured out a easy way to do it.
>
It's surprising how much a "password policies" can affect the keyspace:
http://openwall.info/wiki/john/policy You can see how policies affect the
possible passwords. Once the lengths get up past  12 or so, policy has
little effect on whats who much you have left. If you have 4 policies and 8
characters you do reduce the keyspace by half.

It's different with known-force, or partial passwords. They do help reduce,
but the math just shifts to the remaining characters. 16 through 20 minus 6
is still 10-14 possible characters. There are a variety of ways to attack
the problem, these searches I did might help:
https://www.google.com/#q=site:openwall.com++known+password
http://www.openwall.com/lists/john-users/2010/11/16/4
http://www.openwall.com/lists/john-users/2012/01/23/1
You can also use more than one instance of John with -stdin or -pipe
http://www.openwall.com/lists/john-users/2013/03/27/2

-rich

Powered by blists - more mailing lists

Your e-mail address:

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.