> From: Jacques A. Vidrine [mailto:[EMAIL PROTECTED]]
> Sent: Thursday, January 31, 2002 6:15 AM
> To: Andreas Hasenack; [EMAIL PROTECTED]
> Subject: Re: Paper about kerberos' password security

[...]

> Only if the KDC is correctly configured, which it probably is not.
> MIT, Heimdal, and Windows 2000 implementations default with no pre-
> authentication turned on.[1] Also, even if preauthentication is on,
> one can still abuse the TGS exchange to get the material needed for a
> dictionary attack, unless the KDC administrator has been careful.

[...]

> [1] How do you tune W2K to require preauthentication?

The Win2K KDC requires preauth by default.  It can be configured to selectively NOT 
require preauth on an account-by-account basis by adding the UF_DONT_REQUIRE_PREAUTH 
flag to the user's userAccountControl field.  The MMC users and computers snapin has a 
checkbox for this, if memory serves.  

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