Re: How good is W2K encryption

From: Drew Cooper [MSFT] (dcoop_at_online.microsoft.com)
Date: 05/20/04 

Date: Wed, 19 May 2004 18:53:27 -0700

Having an encryption key (certificate) doesn't mean you also have the
decryption key (private key - not in the certificate).

In a domain, not running as local system, EFS is pretty good - only knowing
the user's password or brute-forcing the crypto gains access to a file's
contents.

XP SP1 and later use AES as their symmetric algorithm by default. And XP
has a fix for the Win2k non-domain loophole. 

-- 
Drew Cooper [MSFT]
This posting is provided "AS IS" with no warranties, and confers no rights.
"Vladimir Katalov" <vkatalov@elcomsoft.com> wrote in message
news:2h12ilF7nebeU1@uni-berlin.de...
> "Peter Kaufman" <no@email.com> wrote in message
> news:an9ma0hrjdhb1i513qvg7ua3m6mjpg5a6f@4ax.com...
> > Assuming one could get a copy of a file or folder, how difficult would
> > it be to break the encryption? Are there commercial services that can
> > do that?  (My M.D. wants to know!)
> >
> > Is there any difference between W2K and XP encryption?
>
> So you mean EFS (Encrypting File System)? Under W2K, it is not very
reliable
> - if you have certificates (encryption keys), the files can be decrypted
> even without
> knowledge of password. Under XP, it is much better, but still can be
broken
> if
> password is known. Have a look at "Advanced EFS Data Recovery":
>
> http://www.elcomsoft.com/aefsdr.html
>
> Some technical details (presentation on BlackHat security conference):
>
>
http://www.blackhat.com/presentations/bh-europe-03/bh-europe-03-malyshev.pdf
>
> -- 
> Sincerely yours,
>   Vladimir
>
> Vladimir Katalov
> Managing Director
> ElcomSoft Co.Ltd.
> Member of Association of Shareware Professionals (ASP)
> Member of Russian Cryptology Association
> mailto:vkatalov@elcomsoft.com
> http://www.elcomsoft.com
>

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