DOCUMENT:Q238349  20-MAY-2002  [iis]
TITLE   :Specially-Malformed Header Creates Denial of Service
PRODUCT :Internet Information Server
PROD/VER:winnt:2.0,2.5,3.0,4.0
OPER/SYS:
KEYWORDS:kbWinNT4sp6fix

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The information in this article applies to:

 - Microsoft Windows NT Server version 4.0, Terminal Server Edition 
 - Microsoft Internet Information Server version 4.0 
 - Microsoft Site Server version 3.0 
 - Microsoft Commercial Internet System versions 2.0, 2.5 
 - Microsoft Site Server version 3.0, Commerce Edition 
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SYMPTOMS
========

A specially-malformed header in a GET request can create a Denial of Service in
the W3 server and use all available memory on the Web server, causing Internet
Information Server (IIS) to stop responding to any request.


RESOLUTION
==========

Windows NT Server or Workstation 4.0 and Internet Information Server
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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/Windows/ServicePacks/

-or-

 - Q152734 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:

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


Windows NT Server 4.0, Terminal Server Edition
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To resolve this problem, obtain the latest service pack for Windows NT Server
4.0, Terminal Server Edition. For additional information, please see the
following article in the Microsoft Knowledge Base:

   Q152734 How to Obtain the Latest Windows NT 4.0 Service Pack


STATUS
======

Microsoft has confirmed this to be a problem in Internet Information Server 4.0.
This problem was first corrected in Windows NT Server version 4.0, Terminal
Server Edition Service Pack 6.Microsoft has confirmed this to be 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.

Additional query words:

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Keywords          : kbWinNT4sp6fix 
Technology        : kbWinNTsearch kbWinNT400search kbWinNTSsearch kbWinNTS400search kbNTTermServ400 kbNTTermServSearch kbSiteServSearch kbiisSearch kbAudDeveloper kbiis400 kbMCISSearch kbMCIS200 kbMCIS250 kbSiteServ300 kbSiteServ300Search
Version           : winnt:2.0,2.5,3.0,4.0
Hardware          : ALPHA x86
Issue type        : kbbug
Solution Type     : kbfix

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Copyright Microsoft Corporation 2002.