Re: Re[2]: Encryption on Laptops?

[Bart.Lansing () kohls com]

Alexander,

I do indeed stand (well, sit..I was never much for keyboarding while
standing) corrected...we do need to take the time to brute the
user'spassword once we own the box.  Still, trivial for anyone who really
wants the files :)

Bart Lansing
Manager, Desktop Services
Kohl's IT


Alexander Lukyanenko <sashman () ua fm> wrote on 03/25/2004 03:49:59 PM:

> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Hello Bart et al,
> ...
> BLkc>    I simply change the
> BLkc>  user account passwords on the box in question, log in as
> BLkc> the user, and voila, I have the
> BLkc>  files.
> Nonsense! The idea of EFS is that the encryption keys
> (`certificates') are itself
> encrypted with user's passwords. If you don't know the password,
> you won't get to the files, and if you'll forcibly change the user's
> password, you'll kill the certificate and render the encrypted files
> unreadable.
> But, the system can still be "opened".
> You can boot with ERD/ntpasswd, change admin's password, boot
> Windows as usual, login, run pwdump/lc4, get the password hashes and then
> brute-force them using lc4 or John The Ripper (don't sure about the
> later being able to deal with NTLM2 hashes). Then you login as the
> user in question with his/her password and voila, you have the files.
> It ain't as easy and fast (you need to bruteforce a password), as just
> changing a user's password, but still possible.
>
> Cheers,
> * * * * * * * * * * * * * * *
> * Alexander V. Lukyanenko   *
> * ma1lt0: sashman ua fm     *
> * ICQ#  : 86195208          *
> * Phone : +380 44 458 07 23 *
> * OpenPGP key ID: 75EC057C  *
> * NIC   : SASH4-UANIC       *
> * * * * * * * * * * * * * * *
> -----BEGIN PGP SIGNATURE-----
> Version: GnuPG v1.2.3 (MingW32)
>
> iD8DBQFAY1QMlz+8e3XsBXwRAsctAJ48/oMjTcreWlX6VoGXOAnVvp5lbACfYrQj
> OCP2z+qFgAVUtiKMZ4AErb0=
> =TGm2
> -----END PGP SIGNATURE-----


CONFIDENTIALITY NOTICE: 
This is a transmission from Kohl's Department Stores, Inc.
and may contain information which is confidential and proprietary.
If you are not the addressee, any disclosure, copying or distribution or use of the contents of this message is 
expressly prohibited.
If you have received this transmission in error, please destroy it and notify us immediately at 262-703-7000.

CAUTION:
Internet and e-mail communications are Kohl's property and Kohl's reserves the right to retrieve and read any message 
created, sent and received.  Kohl's reserves the right to monitor messages by authorized Kohl's Associates at any time
without any further consent.

---------------------------------------------------------------------------
Ethical Hacking at the InfoSec Institute. Mention this ad and get $545 off 
any course! All of our class sizes are guaranteed to be 10 students or less 
to facilitate one-on-one interaction with one of our expert instructors. 
Attend a course taught by an expert instructor with years of in-the-field 
pen testing experience in our state of the art hacking lab. Master the skills 
of an Ethical Hacker to better assess the security of your organization. 
Visit us at: 
http://www.infosecinstitute.com/courses/ethical_hacking_training.html
----------------------------------------------------------------------------