DOCUMENT:Q260205 08-MAY-2002 [iis] TITLE :HTTP Request with Large Number of Dots/Slashes Causes High CPU PRODUCT :Internet Information Server PROD/VER::4.0,5.0 OPER/SYS: KEYWORDS:kbSecurity kbWin2000PreSP1Fix kbWinNT400PreSP7Fix kbWin2000sp1Fix kbgraphxlinkcritical ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Internet Information Server version 4.0 - Microsoft Internet Information Services version 5.0 ------------------------------------------------------------------------------- SYMPTOMS ======== An HTTP GET request with a large number of dots (..) or dot-slashes (././) in the URL can cause high CPU utilization for the Inetinfo process. CAUSE ===== IIS determines how to process a URL based on its extension. When there are a large number of dots or dot-slashes, the Inetinfo process consumes all the CPU power for the time that it takes to determine the right extension. RESOLUTION ========== Windows 2000 ------------ To resolve this problem, obtain the latest service pack for Windows 2000. For additional information, please see the following article in the Microsoft Knowledge Base: Q260910 How to Obtain the Latest Windows 2000 Service Pack The following file is available for download from the Microsoft Download Center: DownloadDownload Q260205_w2k_sp1_x86_en.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=20904) 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. Windows NT 4.0 -------------- A supported fix is now available from Microsoft, but it is only intended to correct the problem described in this article and should be applied only to systems experiencing this specific problem. This fix may receive additional testing at a later time, to further ensure product quality. Therefore, if you are not severely affected by this problem, Microsoft recommends that you wait for the next Windows NT 4.0 that contains this fix. To resolve this problem immediately, download the fix as instructed below or contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information on support costs, please go to the following address on the World Wide Web: http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS NOTE: In special cases, charges that are normally incurred for support calls may be canceled, if a Microsoft Support Professional determines that a specific update will resolve your problem. Normal support costs will apply to additional support questions and issues that do not qualify for the specific update in question. The following files are available for download from the Microsoft Download Center: US English: x86: DownloadDownload Myrdot4i.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=20906) Alpha: DownloadDownload Myrdot4a.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=20906) Chinese (Simplified): x86: DownloadDownload Myrdot4i.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/CN/Myrdot4i.exe) Alpha: DownloadDownload Myrdot4a.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/CN/Myrdot4a.exe) Chinese (Traditional): x86: DownloadDownload Myrdot4i.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/TW/Myrdot4i.exe) Alpha: DownloadDownload Myrdot4a.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/TW/Myrdot4a.exe) Dutch: x86: DownloadDownload Myrdot4i.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/NL/Myrdot4i.exe) Alpha: DownloadDownload Myrdot4a.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/NL/Myrdot4a.exe) French: x86: DownloadDownload Myrdot4i.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/FR/Myrdot4i.exe) Alpha: DownloadDownload Myrdot4a.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/FR/Myrdot4a.exe) German: x86: DownloadDownload Myrdot4i.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/DE/Myrdot4i.exe) Alpha: DownloadDownload Myrdot4a.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/DE/Myrdot4a.exe) Japanese: x86: DownloadDownload Myrdot4i.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/JA/Myrdot4i.exe) Alpha: DownloadDownload Myrdot4a.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/JA/Myrdot4a.exe) Korean: x86: DownloadDownload Myrdot4i.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/KO/Myrdot4i.exe) Alpha: DownloadDownload Myrdot4a.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/KO/Myrdot4a.exe) Portuguese (Brazil): x86: DownloadDownload Myrdot4i.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/PT-BR/Myrdot4i.exe) Alpha: DownloadDownload Myrdot4a.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/PT-BR/Myrdot4a.exe) Spanish: x86: DownloadDownload Myrdot4i.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/ES/Myrdot4i.exe) Alpha: DownloadDownload Myrdot4a.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/ES/Myrdot4a.exe) Swedish: x86: DownloadDownload Myrdot4i.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/SV/Myrdot4i.exe) Alpha: DownloadDownload Myrdot4a.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/SV/Myrdot4a.exe) NOTE: Debug symbol files are required by an administrator to do both kernel and user mode debugging, providing a method to resolve global variables and function names in the loaded executable file. Click the file names below to download the symbol files: US English: x86: DownloadDownload Myrdot4is.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=20906) Alpha: DownloadDownload Myrdot4as.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=20906) Chinese (Simplified): x86: DownloadDownload Myrdot4is.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/CN/Myrdot4is.exe) Alpha: DownloadDownload Myrdot4as.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/CN/Myrdot4as.exe) Chinese (Traditional): x86: DownloadDownload Myrdot4is.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/TW/Myrdot4is.exe) Alpha: DownloadDownload Myrdot4as.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/TW/Myrdot4as.exe) German: x86: DownloadDownload Myrdot4is.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/DE/Myrdot4is.exe) Alpha: DownloadDownload Myrdot4as.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/DE/Myrdot4as.exe) Japanese: x86: DownloadDownload Myrdot4is.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/JA/Myrdot4is.exe) Alpha: DownloadDownload Myrdot4as.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/JA/Myrdot4as.exe) Korean: x86: DownloadDownload Myrdot4is.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/KO/Myrdot4is.exe) Alpha: DownloadDownload Myrdot4as.exe now (http://download.microsoft.com/download/iis40/Patch/Q260205/NT4ALPHA/KO/Myrdot4as.exe) 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 Version Size File name Platform ------------------------------------------------------------ 4/24/00 12:11PM 4.2.743.1 228,496 W3svc.dll x86 4/24/00 12:11PM 4.2.743.1 25,360 Sspifilt.dll x86 4/24/00 12:11PM 4.2.743.1 38,256 Ssinc.dll x86 4/24/00 12:10PM 4.2.743.1 185,760 Infocomm.dll x86 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 ====== Windows 2000 ------------ Microsoft has confirmed this to be a problem in Internet Information Services 5.0. This problem was first corrected in Windows 2000 Service Pack 1. Windows NT 4.0 -------------- Microsoft has confirmed this to be a problem in Internet Information Server 4.0. MORE INFORMATION ================ With this fix installed, the number of dots in the URL are counted. If this number exceeds the default value of 100, an error message occurs. This can also be configured through the registry. To do this, perform the following steps: 1. Start Registry Editor (Regedt32.exe). 2. Locate the following key in the registry: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\w3svc\Parameters\ 3. On the Edit menu, click Add Value, and then add the following registry value: Value Name: MAXDEPTHDOTS Data Type: REG_DWORD Value: 100 4. Quit Registry Editor. For related information about this problem, please visit the following Microsoft Web site: http://www.microsoft.com/technet/security/bulletin/ms00-030.asp For additional security-related information about Microsoft products, please visit the following Microsoft Web site: http://www.microsoft.com/technet/security/default.asp For additional information about how to install Windows 2000 and Windows 2000 fixes at the same time, click the article number below to view the article in the Microsoft Knowledge Base: Q249149 Installing Microsoft Windows 2000 and Windows 2000 Hotfixes Additional query words: security_patch ====================================================================== Keywords : kbSecurity kbWin2000PreSP1Fix kbWinNT400PreSP7Fix kbWin2000sp1Fix kbgraphxlinkcritical Technology : kbiisSearch kbiis500 kbiis400 Version : :4.0,5.0 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.