DOCUMENT:Q298340  15-AUG-2002  [iis]
TITLE   :MS01-044: Patch Available for WebDAV Denial of Service
PRODUCT :Internet Information Server
PROD/VER::5.0
OPER/SYS:
KEYWORDS:kbSecurity kbWin2000PreSP3Fix KbSECVulnerability KbSECBulletin KbSECHack kbWin2000sp3fi

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The information in this article applies to:

 - Microsoft Internet Information Services version 5.0 
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SYMPTOMS
========

In Internet Information Services (IIS) 5.0, a denial of service vulnerability
exists that an attacker could exploit to temporarily disrupt Web services on an
IIS 5.0 server.

Mitigating Factors:

 - The effect of an attack would be temporary. The server would automatically
   resume normal service as soon as the malformed requests stopped arriving.

 - This vulnerability does not provide an attacker with any capability to carry
   out WebDAV requests.

 - This vulnerability does not provide any capability to compromise data on the
   server or gain administrative control over it.

 - This vulnerability only affects IIS 5.0.

CAUSE
=====

This vulnerability occurs because of the way that WebDAV handles a particular
type of very long, invalid request. The net effect is to cause an access
violation that results in the failure of the IIS 5.0 process.

RESOLUTION
==========

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

   Q260910 How to Obtain the Latest Windows 2000 Service Pack

The English version of this fix should have the following file attributes or
later:

   Date         Time  Version        Size     File name
   ------------------------------------------------------
   12-May-2001  1815  5.0.2195.3608  246,032  Httpext.dll


STATUS
======

Microsoft has confirmed that this problem may cause a degree of security
vulnerability in Internet Information Services 5.0. This problem was first
corrected in Windows 2000 Service Pack 3.

MORE INFORMATION
================

This patch also contains fixes for the problems described in the following
Microsoft Knowledge Base article:

   Q297860 IIS 5.0 Security and Post-Windows NT 4.0 SP5 IIS 4.0 Patch Rollup

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

   http://www.microsoft.com/technet/security/bulletin/ms01-044.asp

For additional information about how to obtain a hotfix for Windows 2000
Datacenter Server, click the article number below to view the article in the
Microsoft Knowledge Base:

   Q265173 The Datacenter Program and Windows 2000 Datacenter Server Product

For additional information about how to install multiple hotfixes with only one
reboot, click the article number below to view the article in the Microsoft
Knowledge Base:

   Q296861 Use QChain.exe to Install Multiple Hotfixes with One Reboot

Additional query words: security_patch kbWin2000srp1

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Keywords          : kbSecurity kbWin2000PreSP3Fix KbSECVulnerability KbSECBulletin KbSECHack kbWin2000sp3fix 
Technology        : kbiisSearch kbiis500
Version           : :5.0
Hardware          : x86
Issue type        : kbbug
Solution Type     : kbfix

=============================================================================

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