Access to ProfileList key restricted

The following symptoms may occur:

• When a user logs on to a computer running Windows NT 4.0, a profile other than the user's assigned profile may be loaded and may run malicious files placed in the StartUp folder. The user may be unaware that the profile substitution has taken place.
• A normal domain user can add his or her account to the Domain Administrators group and obtain the permissions of that group by copying the profile to a self-deleting batch file and specifying the path to that file in the ProfileImagePath value in the Administrator's ProfileList key. The next time someone uses the Administrator account and password to log on, the batch file runs and adds that user's profile to the Domain Administrators group.
• Users may be able to bypass mandatory profiles.

This behavior occurs in Windows NT 4.0 because the registry key listed below grants the SetValue permission to the Everyone group by default, so that any user (even guests) can edit the information in the ProfileList registry key and its subkeys: Editing these keys can be performed locally or remotely, and setting permissions in the Access Control List (ACL) on the Winreg key (HKEY_LOCAL_MACHINE\System) does not limit remote access because the path to the CurrentVersion key is an allowed path and can be edited regardless of the permissions assigned to the Winreg key.

Windows NT Server or Workstation 4.0

To resolve this problem, obtain the latest service pack for Windows NT 4.0 or the individual software update. For information on obtaining the latest service pack, please go to:

• http://www.microsoft.com/downloads/details.aspx?familyid=E396D059-E402-46EF-B095-A74399E25737&displaylang=en/ (http://www.microsoft.com/Windows/ServicePacks/)
• 152734  (http://support.microsoft.com/kb/152734/ ) How to obtain the latest Windows NT 4.0 service pack

For information on obtaining the individual software update, contact Microsoft Product Support Services. For a complete list of Microsoft Product Support Services phone numbers and information on support costs, please go to the following address on the World Wide Web: When you apply Windows NT 4.0 Service Pack 6 (SP6), the default permission on the Everyone group is set to read access only. Also, the process created by Winlogon.exe creates the user's Security Identifier (SID) subkey in the System account, instead of under the CurrentVersion key, and then writes the necessary values to the ProfileList key.

Windows NT Server 4.0, Terminal Server Edition

To resolve this problem, obtain the latest service pack for Windows NT Server 4.0, Terminal Server Edition. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

Microsoft has confirmed that this is a problem in Windows NT 4.0 and Windows NT Server 4.0, Terminal Server Edition.

This problem was first corrected in Windows NT Server 4.0 Service Pack 6 and Windows NT Server 4.0, Terminal Server Edition Service Pack 6.

For more information about making your Windows NT 4.0 installation secure, see the "Securing Microsoft Windows NT Installation" white paper at the following Microsoft Web site: