Thanks Guy - I'll take that hint into consideration as well. 
 
Mind you, instead of fooling around with the SDDL version of the defaultSecurityDescriptor of any object in AD's schema, it's much easier to edit it via the Schema Mgr MMC => go to the respective object and edit the default ACLs via the "Default Security" tab (in Win2000 this tab is called "Security", but also refers to the default security of new objects of this type).
 
This way I've also adjusted the default rights for users, so that the SELF sec.principal doesn't have any special write permissions on the user object (protecting AD from unwanted updates by users). We then grant inherited permissions for SELF at the OU level for only those attributes of the user objects which the users are supposed to be allowed to edit (which aren't many).  This saves us from internal "attacks" such as users uploading a large picture file to the thumbnail attribute etc.
 
Thanks,
Guido

From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Guy Teverovsky
Sent: Tuesday, November 09, 2004 1:11 AM
To: [EMAIL PROTECTED]
Subject: RE: [ActiveDir] Issues with Win 2k3 Inplace Upgrade - Registry Security

What we did in our environment was:

-         disabled the links of DDP/DDCP to domain object and Domain Controllers OU

-         remove “Group Policy Creator Owners” from the ACL of “CN=Policies,CN=System,DC=domain,DC=com” and added our own group with permissions to create objects in the container.

-         changed the defaultSecurityDescriptor attribute of Group-Policy-Container object, trimmed the Domain Admins to read-only and introduced a new security group with full permissions over newly created GPOs (SDDL is an ugly thing to work with, so if you are interested in quick and dirty SDDL parser I wrote, grab it from here: http://www.petri.co.il/forums/download.php?id=43 ). This way the GPOs are created with ACL which does not allow default groups to change it (see http://www.jsiinc.com/SUBL/tip5500/rh5528.htm for details)

-         created new GPOs to replace DDP/DDCP (those were created with the adjusted ACL)

 

Guy

 


From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Willem Kasdorp
Sent: Monday, November 08, 2004 5:40 PM
To: [EMAIL PROTECTED]
Subject: RE: [ActiveDir] Issues with Win 2k3 Inplace Upgrade - Registry Security

 

I have had similar issues before at customer sites with apps modifying the DDP and DDCP, although none this bad. ADMT is a notorious offender.  I am seriously tempted to fix it in the following way:

 

-          create a new DDP/DDCP (new name of course) with highest prio. Edit any additional settings in the new policies.

-          Remove write for Domain Admins on the DDP/DDCP, and instead create an additional group for write permissions. This group is empty by default.

 

 

This story might just trigger me to do it…

 

--

    Regards, Willem

 


From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Grillenmeier, Guido
Sent: Monday, November 08, 2004 2:57 PM
To: [EMAIL PROTECTED]
Subject: [ActiveDir] Issues with Win 2k3 Inplace Upgrade - Registry Security

 

Hello folks,

 

I've just had a very curious issue at a customer, which took us a while to figure out. You should all be aware of this as it could hurt you as well.  After testing everything successfully in the lab (and ADPREPing the production forest + domains), we've inplace-upgraded the first production DC from Win2000 to Win2003 and it failed with errors such as a crashing LSASS and a DHCP service, which couldn't start due to access violation etc.

 

It turns out that this was caused due to a lengthy list of policy settings on the Def Domain and Def DC Policy, which configured Security (ACL) over one hundred registry keys and File System folders and files.

 

The resulting permissions were ok for Windows 2000, but incompatible with Windows Server 2003 - e.g. the DHCP Client Service and the TCPIP Service require specific permissions on their respective registry keys for the DHCP service to start via the new Network Service account. I see other's in this list have also had issues with the DCHP service, which may be related to the same thing.  

Although we now fixed the issue by cleaning the policies and un-promoting the DC and reinstalling it from scratch (since the 2003 OS's default permissions were effectively overwritten due to the policy), I am looking for clues on how these weird settings were introduced to the Def Dom and the Def DC policy in the first place?  

 

The settings were definitely not added manually "by accident" -  more likely by some whacky setup routine.  Does anybody have an ideas or experience with respect to services/apps which could have changed the domain policies in this way?

 

 

Thanks for any feedback,

Guido

 

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