DOCUMENT:Q271652 15-MAY-2002 [winnt] TITLE :Patch for Malformed URL Vulnerability That Disables Web Server PRODUCT :Microsoft Windows NT PROD/VER::4.0 OPER/SYS: KEYWORDS:kbSecurity kbWinNT400PreSP7Fix kbgraphxlinkcritical KbSECVulnerability KbSECBulletin ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Server version 4.0 - Microsoft Windows NT Server, Enterprise Edition version 4.0 - Microsoft Windows NT Workstation version 4.0 - Microsoft Windows NT Server version 4.0, Terminal Server Edition - Microsoft Internet Information Server version 4.0 ------------------------------------------------------------------------------- SYMPTOMS ======== Microsoft has released a patch that eliminates a security vulnerability in Internet Information Server (IIS). This vulnerability could enable a malicious user to send malformed URLs that prevent a Web server from being able to respond to requests for Web pages, FTP services, or any other services that are provided by IIS. NOTE: This vulnerability does not provide the opportunity to compromise any data on the server or compromise any administrative privileges on the server. You can place the server back in service by restarting the IIS service. You can find additional information about this vulnerability and the patch at the following Microsoft Web site: http://www.microsoft.com/technet/security/bulletin/ms00-063.asp Frequently asked questions about this vulnerability and the patch are available at the following Microsoft Web site: http://www.microsoft.com/technet/security/bulletin/fq00-063.asp CAUSE ===== The vulnerability is caused by a problem in Windows NT 4.0 that causes IIS to mishandle a particular type of invalid URL under certain conditions. RESOLUTION ========== Windows NT 4.0 -------------- To resolve this problem, obtain the individual package referenced below or obtain the Windows NT 4.0 Security Rollup Package. For additional information on the SRP, click the article number below to view the article in the Microsoft Knowledge Base: Q299444 Post-Windows NT 4.0 Service Pack 6a Security Rollup Package (SRP) The following file is available for download from the Microsoft Download Center: DownloadDownload Q271652i.exe now (http://www.microsoft.com/downloads/release.asp?ReleaseID=24403) For additional information about how to download Microsoft Support files, click the article number below to view the article in the Microsoft Knowledge Base: Q119591 How to Obtain Microsoft Support Files from Online Services Microsoft used the most current virus detection software available on the date of posting to scan this file for viruses. After it is posted, the file is housed on secure servers that prevent any unauthorized changes to the file. The English version of this fix should have the following file attributes or later: Date Time Size File name Platform --------------------------------------------------------------- 08/17/2000 07:43p 375,056 Kernel32.dll x86 08/30/2000 07:07p 375,056 Kernel32.dll x86 (Uniprocessor) 08/17/2000 08:42p 590,096 Kernel32.dll Alpha 08/17/2000 08:42p 590,096 Kernel32.dll Alpha (Uniprocessor) 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 additional information about the SRP, click the article number below to view the article in the Microsoft Knowledge Base: Q317636 Windows NT Server 4.0, Terminal Server Edition, Security Rollup Package STATUS ====== Microsoft has confirmed that this problem could result in some degree of security vulnerability in Microsoft Windows NT 4.0. Additional query words: security_patch ====================================================================== Keywords : kbSecurity kbWinNT400PreSP7Fix kbgraphxlinkcritical KbSECVulnerability KbSECBulletin Technology : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTSsearch kbWinNTSEntSearch kbWinNTSEnt400 kbWinNTS400search kbWinNTS400 kbNTTermServ400 kbNTTermServSearch kbiisSearch kbiis400 Version : :4.0 Hardware : ALPHA 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.