Locking Down WebDAV Through ACL Still Allows PUT and DELETE Requests (307934)


The information in this article applies to:

  • Microsoft Internet Information Services 5.0
  • Microsoft Internet Information Services version 5.1
This article was previously published under Q307934

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

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:

319733 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:

319733 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:

241520 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:

311401 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:

260910 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.
Modification Type:MinorLast Reviewed:11/17/2005
Keywords:kbHotfixServer kbQFE kbbug kbfix kbSecurity kbWin2000PreSP3Fix kbWin2000sp3fix KB307934
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