Q260838: MS00-031: IIS Stops Servicing HTR Requests
Article: Q260838
Product(s): Internet Information Server
Version(s): 4.0,5.0
Operating System(s):
Keyword(s): kbSecurity kbWin2000PreSP1Fix kbWinNT400PreSP7Fix kbWin2000sp1Fix kbgraphxlinkcritical
Last Modified: 16-MAY-2002
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The information in this article applies to:
- Microsoft Internet Information Server version 4.0
- Microsoft Internet Information Services version 5.0
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SYMPTOMS
========
If a malicious user provides a password change request that is missing an
expected delimiter, the algorithm conducts an unbounded search. This prevents
the servicing of additional HTR requests, and can also slow the overall response
of the server.
CAUSE
=====
The body of the request for a HTR page is assumed to be valid.
RESOLUTION
==========
Windows 2000
------------
The original release of this fix is available in Windows 2000 Service Pack 1. For
additional information on Windows 2000 Service Pack 1, click the article number
below to view the article in the Microsoft Knowledge Base:
Q260910 How to Obtain the Latest Windows 2000 Service Pack
For additional information about what the updated package fixes, click the
article numbers below to view the articles in the Microsoft Knowledge Base:
Q267560 Changing the URL in a Specific Manner May Expose Contents of a File
Q267559 GET on .Htr File Can Cause a "Denial of Service" or Enable Directory
Browsing
Q260069 Malformed HTR Request Returns Source Code for ASP Scripting Files
A supported fix is now available from Microsoft, but it is only intended to
correct the problem described in this article and should be applied only to
systems experiencing this specific problem. This fix may receive additional
testing at a later time, to further ensure product quality. Therefore, if you
are not severely affected by this problem, Microsoft recommends that you wait
for the next Windows 2000 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:
http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS
NOTE: In special cases, charges that are normally incurred for support calls may
be canceled, if a Microsoft Support Professional determines that a specific
update will resolve your problem. Normal support costs will apply to additional
support questions and issues that do not qualify for the specific update in
question.
The following file is available for download from the Microsoft Download Center:
DownloadDownload Q267559_w2k_sp2_x86_en.exe now
(http://www.microsoft.com/Downloads/Release.asp?ReleaseID=22708)
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. After it is 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 Version Size File name
-----------------------------------------------------
07/07/2000 03:17p 5.00.2195.2100 46,352 Ism.dll
Windows NT 4.0
--------------
A supported fix is now available from Microsoft, but it is only intended to
correct the problem described in this article and should be applied only to
systems experiencing this specific problem. This fix may receive additional
testing at a later time, to further ensure product quality. Therefore, if you
are not severely affected by this problem, Microsoft recommends that you wait
for the next Windows NT 4.0 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:
http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS
NOTE: In special cases, charges that are normally incurred for support calls may
be canceled, if a Microsoft Support Professional determines that a specific
update will resolve your problem. Normal support costs will apply to additional
support questions and issues that do not qualify for the specific update in
question.
The following file is available for download from the Microsoft Download Center:
US English:
x86: DownloadDownload Ismpst4i.exe now
(http://www.microsoft.com/Downloads/Release.asp?ReleaseID=20905)
Alpha: DownloadDownload Ismpst4a.exe now
(http://www.microsoft.com/Downloads/Release.asp?ReleaseID=20905)
Chinese (Simplified):
x86: DownloadDownload Ismpst4i.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/CN/Ismpst4i.exe)
x86 Symbols: DownloadDownload Ismpst4is.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/CN/Ismpst4is.exe)
Alpha: DownloadDownload Ismpst4a.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/CN/Ismpst4a.exe)
Alpha Symbols: DownloadDownload Ismpst4as.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/CN/Ismpst4as.exe)
Chinese (Traditional):
x86: DownloadDownload Ismpst4i.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/TW/Ismpst4i.exe)
x86 Symbols: DownloadDownload Ismpst4is.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/TW/Ismpst4is.exe)
Alpha: DownloadDownload Ismpst4a.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/TW/Ismpst4a.exe)
Alpha Symbols: DownloadDownload Ismpst4as.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/TW/Ismpst4as.exe)
German:
x86: DownloadDownload Ismpst4i.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/DE/Ismpst4i.exe)
x86 Symbols: DownloadDownload Ismpst4is.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/DE/Ismpst4is.exe)
Alpha: DownloadDownload Ismpst4a.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/DE/Ismpst4a.exe)
Alpha Symbols: DownloadDownload Ismpst4as.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/DE/Ismpst4as.exe)
Japanese:
x86: DownloadDownload Ismpst4i.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/JA/Ismpst4i.exe)
x86 Symbols: DownloadDownload Ismpst4is.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/JA/Ismpst4is.exe)
Alpha: DownloadDownload Ismpst4a.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/JA/Ismpst4a.exe)
Alpha Symbols: DownloadDownload Ismpst4as.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/JA/Ismpst4as.exe)
Korean:
x86: DownloadDownload Ismpst4i.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/KO/Ismpst4i.exe)
x86 Symbols: DownloadDownload Ismpst4is.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/KO/Ismpst4is.exe)
Alpha: DownloadDownload Ismpst4a.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/KO/Ismpst4a.exe)
Alpha Symbols: DownloadDownload Ismpst4as.exe now
(http://download.microsoft.com/download/iis40/Patch/Q260838/NT4ALPHA/KO/Ismpst4as.exe)
Microsoft Windows NT Server version 4.0, Terminal Server Edition
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To resolve this problem, obtain the Windows NT Server 4.0, Terminal Server
Edition, Security Rollup Package (SRP). For additional information about the
SRP, click the article number below to view the article in the Microsoft
Knowledge Base:
Q317636 Windows NT Server 4.0, Terminal Server Edition, Security Rollup
Package
STATUS
======
Windows 2000
------------
Microsoft has confirmed this problem could result in some degree of security
vulnerability in Internet Information Services 5.0. This problem was first
corrected in Windows 2000 Service Pack 1.
Windows NT 4.0
--------------
Microsoft has confirmed this problem could result in some degree of security
vulnerability in Internet Information Server 4.0.
MORE INFORMATION
================
For related information about this problem, please visit the following Microsoft
Web site:
http://www.microsoft.com/technet/security/bulletin/ms00-031.asp
For additional security-related information about Microsoft products, please
visit the following Microsoft Web site:
http://www.microsoft.com/security/
For additional information about what else is fixed by this update, click the
article number below to view the article in the Microsoft Knowledge Base:
Q260069 Malformed HTR Request Returns Source Code for ASP Scripting Files
Additional query words: security_patch DoS denial of service
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Keywords : kbSecurity kbWin2000PreSP1Fix kbWinNT400PreSP7Fix kbWin2000sp1Fix kbgraphxlinkcritical
Technology : kbiisSearch kbiis500 kbiis400
Version : :4.0,5.0
Hardware : ALPHA x86
Issue type : kbbug
Solution Type : kbfix
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