Microsoft KB Archive/277873

= MS00-086: Patch available for &quot;Web server file request parsing&quot; vulnerability =

Article ID: 277873

Article Last Modified on 2/13/2007

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APPLIES TO


 * Microsoft Internet Information Services 5.0
 * Microsoft Internet Information Server 4.0

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This article was previously published under Q277873



We strongly recommend that all users upgrade to Microsoft Internet Information Services (IIS) version 6.0 running on Microsoft Windows Server 2003. IIS 6.0 significantly increases Web infrastructure security. For more information about IIS security-related topics, visit the following Microsoft Web site:

http://www.microsoft.com/technet/security/prodtech/IIS.mspx



SYMPTOMS
Microsoft has released a patch that eliminates a serious security vulnerability in Microsoft Internet Information Services (IIS) 5.0 or Internet Information Server 4.0. When IIS receives a valid request for an executable file, it passes the name of the requested file to the underlying operating system for processing. However, because of an implementation flaw, it is possible to create a specially malformed file request that contains both a file name and one or more operating system commands. When it receives such a request, IIS passes the entire string to the operating system, which first processes the file, and then executes the commands. The file must reside in a folder to which the user has execute permissions, but it does not necessarily need to be an executable file.

The ability to execute operating system commands on a Web server can enable a malicious user to take virtually any action that an interactively logged on user can take. Although this does not give the malicious user administrative control over the server, it can nevertheless allow him to cause widespread damage. He could, for instance, add, delete or change files on the server, run code that was already on the server, or upload and run the code of his choice.

For more information on this vulnerability, see the following Microsoft Web site:

http://www.microsoft.com/technet/security/bulletin/ms00-086.mspx



Windows 2000
To resolve this problem, obtain the latest service pack for Windows 2000. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

260910 How to obtain the latest Windows 2000 service pack

The following files are available for download from the Microsoft Download Center:

English Language Version

Chinese (Simplified) Language Version

Chinese (Traditional) Language Version

Czech Language Version

Danish Language Version

Dutch Language Version

Finnish Language Version

French Language Version

German Language Version

Greek Language Version

Hungarian Language Version

Italian Language Version

Japanese Language Version

Norwegian Language Version

Polish Language Version

Portuguese (Brazilian) Language Version

Portuguese Language Version

Russian Language Version

Spanish Language Version

Swedish Language Version

Turkish Language Version

For more information about how to download Microsoft support files, click the following article number to view the article in the Microsoft Knowledge Base:

119591 How to obtain Microsoft support files from online services

Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help 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 --  11/27/2000  10:12p  5.0.2195.2785  122,640  Iisrtl.dll 11/27/2000 10:12p  5.0.2195.2784  357,136  W3svc.dll

Windows NT 4.0
A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that this article describes. Apply it only to systems that are experiencing this specific problem.

To resolve this problem, contact Microsoft Product Support Services to obtain the hotfix. For a complete list of Microsoft Product Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:

http://support.microsoft.com/contactus/?ws=support

Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The following files are available for download from the Microsoft Download Center:

Note It is important that you have installed the latest service pack before you apply this patch.

US English:

Download Arbexei.exe now

Chinese (Simplified):

Download Arbexei.exe now

Chinese (Traditional):

Download Arbexei.exe now

For more information about how to download Microsoft support files, click the following article number to view the article in the Microsoft Knowledge Base:

119591 How to obtain Microsoft support files from online services

Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help 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 11/08/2000 03:29p  4.2.753.1  214,544  adsiis.dll 11/09/2000 05:32p  4.2.753.1  330,672  asp.dll 11/08/2000 02:39p              11,396  httpext.h   11/09/2000  05:38p  4.2.753.1   55,904  httpodbc.dll 11/08/2000 03:29p  4.2.753.1   98,912  iischema.dll 11/08/2000 02:39p              28,851  iiscnfg.h   11/08/2000  03:27p  4.2.753.1  185,792  infocomm.dll 11/09/2000 05:38p  4.2.753.1   38,256  ssinc.dll 11/08/2000 03:28p  4.2.753.1   25,360  sspifilt.dll 11/09/2000 05:37p  4.2.753.1  229,008  w3svc.dll Note Due to file dependencies, this hotfix requires Microsoft Windows NT 4.0 Service Pack 5 or Service Pack 6a.

Microsoft Windows NT Server version 4.0, Terminal Server Edition
To resolve this problem, obtain the Windows NT Server 4.0, Terminal Server Edition, Security Rollup Package (SRP). For more information about the SRP, click the following article number to view the article in the Microsoft Knowledge Base:

317636 Windows NT Server 4.0, Terminal Server Edition, Security Rollup Package



Windows 2000
Microsoft has confirmed that this is a problem in Internet Information Services 5.0. This problem was first corrected in Windows 2000 Service Pack 2.

Windows NT 4.0
Microsoft has confirmed that this is a problem in Internet Information Server 4.0.



MORE INFORMATION
For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:

824684 Description of the standard terminology that is used to describe Microsoft software updates

Additional query words: security_patch

Keywords: kbhotfixserver kbqfe kbbug kbfix kbgraphxlinkcritical kbsecurity kbwin2000presp2fix KB277873

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