MS01-044: IIS Loads ISAPI Extension In-Process Even When Application Is Marked for High Isolation (294774)


The information in this article applies to:

  • Microsoft Internet Information Services 5.0
This article was previously published under Q294774

SYMPTOMS

If an ISAPI DLL has the same name as a DLL that is listed in the InProcessIsapiApps metabase entry, Internet Information Services (IIS) loads the ISAPI extension in-process even when the Application is marked for High Isolation.

CAUSE

When IIS reads the list of InProcessIsapiApps from the metabase, it makes two copies of each entry: one copy of the entire path and one copy of only the DLL. This allows for relative path matching.

RESOLUTION

To resolve this problem, either obtain the hotfix referenced in this section or Windows 2000 Security Rollup Package 1 (SRP1). 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

The following file is available for download from the Microsoft Download Center:

DownloadDownload Q301625_W2K_SP3_x86_en.exe now

NOTE: This patch can be installed on systems running Windows 2000 Service Pack 1 or Windows 2000 Service Pack 2. You must reapply the security rollup patch after you install a Windows 2000 Service Pack.

Release Date: August 15, 2001

For additional 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 to 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
   ----------------------------------------------------
   31-May-2001 15:32  5.0.2195.3649  353,040  W3svc.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:

297860 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.mspx

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:

265173 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:

296861 Use QChain.exe to Install Multiple Hotfixes with One Reboot

Modification Type:MinorLast Reviewed:10/10/2006
Keywords:kbHotfixServer kbQFE kbbug kbfix KbSECHack kbSecurity KbSECVulnerability kbWin2000PreSP3Fix kbWin2000sp3fix KB294774
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