DOCUMENT:Q252693 08-MAY-2002 [iis] TITLE :Chunked Encoding Request with No Data Causes IIS Memory Leak PRODUCT :Internet Information Server PROD/VER::4.0 OPER/SYS: KEYWORDS:kbSecurity kbWinNT400PreSP7Fix kbgraphxlinkcritical ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Internet Information Server version 4.0 ------------------------------------------------------------------------------- SYMPTOMS ======== A repetitive attack using a specially malformed request may cause Internet Information Server (IIS) to use a large amount of memory, and eventually cause the service to fail. This problem can occur when the client uses the Transfer-Encoding: chunked header in its request. RESOLUTION ========== 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. To resolve this problem, 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 Chkenc4i.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19761) Alpha: DownloadDownload Chkenc4a.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19762) Chinese (Simplified): x86: DownloadDownload Chkenc4i.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19879) Alpha: DownloadDownload Chkenc4a.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19879) Chinese (Traditional): x86: DownloadDownload Chkenc4i.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19880) Alpha: DownloadDownload Chkenc4a.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19880) Dutch: x86: DownloadDownload Chkenc4i.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=27728) Alpha: DownloadDownload Chkenc4a.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=27728) French: x86: DownloadDownload Chkenc4i.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=27730) Alpha: DownloadDownload Chkenc4a.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=27730) German: x86: DownloadDownload Chkenc4i.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19881) Alpha: DownloadDownload Chkenc4a.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19881) Japanese: x86: DownloadDownload Chkenc4i.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19882) Alpha: DownloadDownload Chkenc4a.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19882) Korean: x86: DownloadDownload Chkenc4i.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19883) Alpha: DownloadDownload Chkenc4a.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19883) Portuguese (Brazil): x86: DownloadDownload Chkenc4i.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=27729) Alpha: DownloadDownload Chkenc4a.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=27729) Spanish: x86: DownloadDownload Chkenc4i.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=27731) Alpha: DownloadDownload Chkenc4a.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=27731) Swedish: x86: DownloadDownload Chkenc4i.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=27732) Alpha: DownloadDownload Chkenc4a.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=27732) 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 Chkenc4is.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19761) Alpha: DownloadDownload Chkenc4as.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19762) Chinese (Simplified): x86: DownloadDownload Chkenc4is.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19879) Alpha: DownloadDownload Chkenc4as.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19879) Chinese (Traditional): x86: DownloadDownload Chkenc4is.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19880) Alpha: DownloadDownload Chkenc4as.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19880) German: x86: DownloadDownload Chkenc4is.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19881) Alpha: DownloadDownload Chkenc4as.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19881) Japanese: x86: DownloadDownload Chkenc4is.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19882) Alpha: DownloadDownload Chkenc4as.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19882) Korean: x86: DownloadDownload Chkenc4is.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19883) Alpha: DownloadDownload Chkenc4as.exe now (http://www.microsoft.com/Downloads/Release.asp?ReleaseID=19883) The English version of this fix should have the following file attributes or later: Date Time Version Size File name Platform ---------------------------------------------------------------------- 1/28/2000 02:32:16p 4.2.739.1 185,760b Infocomm.dll x86 1/28/2000 02:33:10p 4.2.739.1 38,256b Ssinc.dll x86 1/28/2000 02:33:18p 4.2.739.1 25,360b Sspifilt.dll x86 1/28/2000 02:32:58p 4.2.739.1 228,480b W3svc.dll x86 1/28/2000 05:32:05p 4.2.739.1 304,400b Infocomm.dll Alpha 1/28/2000 05:53:00p 4.2.739.1 60,176b Ssinc.dll Alpha 1/28/2000 05:53:07p 4.2.739.1 39,696b Sspifilt.dll Alpha 1/28/2000 05:32:49p 4.2.739.1 383,760b W3svc.dll Alpha 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 this to be a problem in Internet Information Server 4.0. Additional query words: security_patch tsesrp ====================================================================== Keywords : kbSecurity kbWinNT400PreSP7Fix kbgraphxlinkcritical Technology : 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.