DOCUMENT:Q229441  16-MAY-2002  [winnt]
TITLE   :Denial of Service Attack with Duplicate Objects Between Sessions
PRODUCT :Microsoft Windows NT
PROD/VER:winnt:4.0
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Windows NT Server version 4.0, Terminal Server Edition 
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SYMPTOMS
========

A possible denial of service attack exists in Windows NT Server 4.0, Terminal
Server Edition when objects containing session-specific information are
duplicated between sessions.

CAUSE
=====

Desktop and window station objects are system objects allocated by the object
manager in global system memory and are accessible from all sessions. The
problem occurs when a handle to a dekstop or window station is opened from one
session and duplicated to a program running in another session.

RESOLUTION
==========

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

 - http://www.microsoft.com/windows/servicepacks/

-or-

 - Q152734 How to Obtain the Latest Windows NT Server 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:

   http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS


STATUS
======

Microsoft has confirmed this to be a problem in Windows NT Server 4.0, Terminal
Server Edition. This problem was first corrected in Windows NT Server 4.0,
Terminal Server Edition Service Pack 4.

Additional query words:

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Keywords          :  
Technology        : kbWinNTsearch kbWinNT400search kbWinNTSsearch kbWinNTS400search kbNTTermServ400 kbNTTermServSearch
Version           : winnt:4.0
Issue type        : kbbug
Solution Type     : kbfix

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