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Service Control Manager Named Pipe Impersonation Vulnerability

The information in this article applies to:
  • Microsoft Windows 2000 Professional
  • Microsoft Windows 2000 Server
  • Microsoft Windows 2000 Advanced Server


It may be possible for a non-privileged user to elevate their existing security context to that of a service that was started by Service Control Manager (SCM). A malicious user could use a named pipe connection to instruct a Windows 2000-based computer to start a pre-defined process that has a security permission higher than the actual security permission that is assigned to the user.


A supported fix that corrects this problem is now available from Microsoft, but it has not been fully regression tested and should be applied only to computers that are experiencing this specific problem. If you are not severely affected by this specific problem, Microsoft recommends that you wait for the next Windows 2000 service pack that contains this fix.

To resolve this problem immediately, download the fix as instructed below or contact Microsoft Product Support Services to obtain the fix. 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:
The following file is available for download from the Microsoft Download Center. Click the file name below to download the file:
For additional information about how to download Microsoft Support files, click the article number below to view the article in the Microsoft Knowledge Base:
Q119591 How to Obtain Microsoft Support Files from Online Services
Microsoft used the most current virus detection software available on the date of posting to scan this file for viruses. Once posted, the file is housed on secure servers that prevent any unauthorized changes to the file.

The English version of this fix should have the following file attributes or later:
   Date       Time     Size      File name
   07/25/00   06:18p   707,344   Kernel32.dll
   07/25/00   06:17p   85,776    Services.exe 


Microsoft has confirmed this to be a problem in Microsoft Windows 2000.


For additional information about how to install Windows 2000 and Windows 2000 hotfixes at the same time, click the article number below to view the article in the Microsoft Knowledge Base:

Q249149 Installing Microsoft Windows 2000 and Windows 2000 Hotfixes

For related information about this problem, please visit the following Microsoft Web site:
For additional security-related information about Microsoft products, please visit the following Microsoft Web site:

Additional query words:

Keywords : kbSecurity kbWin2000PreSP2Fix
Issue type : kbbug
Technology : kbwin2kAdvSer kbwin2kAdvSerSearch kbwin2kS kbwin2kSSearch kbwin2kSearch kbwin2kProSearch kbwin2kPro

Last Reviewed: November 15, 2000
2000 Microsoft Corporation. All rights reserved. Terms of Use.

Article ID: Q269523

Last Reviewed:
November 15, 2000

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