DOCUMENT:Q307934  15-AUG-2002  [iis]
TITLE   :Locking Down WebDAV via ACL Still Allows PUT & DELETE Requests
PRODUCT :Internet Information Server
PROD/VER::5.0
OPER/SYS:
KEYWORDS:kbSecurity kbCOMIS kbWin2000PreSP3Fix kbWinXPpreSP1fix kbWin2000sp3fix

======================================================================
-------------------------------------------------------------------------------
The information in this article applies to:

 - Microsoft Internet Information Services version 5.0 
 - Microsoft Internet Information Services version 5.1 
-------------------------------------------------------------------------------

SYMPTOMS
========

HTTP PUT and DELETE requests are handled by Web Distributed Authoring and
Versioning (WebDAV) in Internet Information Services (IIS) 5.0 and 5.1. Because
WebDAV may expose unnecessary functionality, Microsoft recommends that you
disable WebDAV by setting a deny EXECUTE access control list (ACL) on
Httpext.dll. PUT and DELETE requests can still succeed even after you lock down
Httpext.dll.

CAUSE
=====

When IIS fails to load Httpext.dll, the core Web service has internal routines
to handle PUT requests; however, these internal routines have not been tested
because disabling DAV is not a configuration that is by design in IIS. You do
not have to set a deny EXECUTE ACL on Httpext.dll because a new registry value
is exposed to disable WebDAV.

RESOLUTION
==========

 - Internet Information Services 5.1
 - Internet Information Services 5.0

Internet Information Services 5.1
---------------------------------

The update for this problem is included in the "MS02-018: April 2002 Cumulative
Patch for Internet Information Services". For additional information about how
to obtain this patch, click the article number below to view the article in the
Microsoft Knowledge Base:

   Q319733 MS02-018: April 2002 Cumulative Patch for Internet Information
   Services

Internet Information Services 5.0
---------------------------------

The update for this problem is included in the "MS02-018: April 2002 Cumulative
Patch for Internet Information Services". For additional information about how
to obtain this patch, click the article number below to view the article in the
Microsoft Knowledge Base:

   Q319733 MS02-018: April 2002 Cumulative Patch for Internet Information
   Services

For additional information on a registry value introduced in the Windows 2000
Security Rollup Package 1 (SRP1), click the article number below to view the
article in the Microsoft Knowledge Base:

   Q241520 How to Disable WebDAV for IIS 5.0

For additional information about SRP1, click the article number below to view the
article in the Microsoft Knowledge Base:

   Q311401 Windows 2000 Security Rollup Package 1 (SRP1), January 2002

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

STATUS
======

Internet Information Services 5.1
---------------------------------

Microsoft has confirmed that this is a problem in Microsoft Internet Information
Services 5.1.

Internet Information Services 5.0
---------------------------------

Microsoft has confirmed that this is a problem in Microsoft Internet Information
Services 5.0. This problem was first corrected in Windows 2000 Service Pack 3.

Additional query words: kbIISCom security_patch kbwin2000srp1 iislockd srp kbIIS400500510April2002Rollup

======================================================================
Keywords          : kbSecurity kbCOMIS kbWin2000PreSP3Fix kbWinXPpreSP1fix kbWin2000sp3fix 
Technology        : kbiisSearch kbiis500 kbiis510
Version           : :5.0
Hardware          : x86
Issue type        : kbbug
Solution Type     : kbfix

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

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS
PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND.  MICROSOFT DISCLAIMS
ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  IN NO
EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR
ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL,
CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF
MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES.  SOME STATES DO NOT ALLOW THE EXCLUSION
OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES
SO THE FOREGOING LIMITATION MAY NOT APPLY.

Copyright Microsoft Corporation 2002.