From secnotif@MICROSOFT.COM Tue Aug 1 00:19:40 2000 From: Microsoft Product Security Resent-From: mea culpa To: MICROSOFT_SECURITY@ANNOUNCE.MICROSOFT.COM Resent-To: jericho@attrition.org Date: Fri, 28 Jul 2000 17:47:56 -0700 Subject: Microsoft Security Bulletin (MS00-052) The following is a Security Bulletin from the Microsoft Product Security Notification Service. Please do not reply to this message, as it was sent from an unattended mailbox. ******************************** -----BEGIN PGP SIGNED MESSAGE----- Microsoft Security Bulletin (MS00-052) - -------------------------------------- Patch Available for "Relative Shell Path" Vulnerability Originally posted: July 28, 2000 Summary ======= Microsoft has released a patch that eliminates a security vulnerability in Microsoft(r) Windows NT(r) 4.0 and Windows(r) 2000. Under certain conditions, the vulnerability could enable a malicious user to cause code of his choice to run when another user subsequently logged onto the same machine. Frequently asked questions regarding this vulnerability and the patch can be found at http://www.microsoft.com/technet/security/bulletin/fq00-052.asp Issue ===== The registry entry that specifies the Windows Shell executable (Explorer.exe) provides a relative, rather than absolute, path name. (As discussed in the FAQ, it does this because of legacy application compatibility concerns). Because of the circumstances in place at system startup time, the normal search order would cause any file named Explorer.exe in the %Systemdrive%\ directory to be loaded in place of the bona fide version. This could provide an opportunity for a malicious user to cause code of his choice to run when another user subsequently logged onto the same machine. Under normal conditions, the malicious user could only exploit this vulnerability on machines that he could interactively log onto. As a result, workstations and terminal servers would be the machines primarily at risk. If standard security recommendations have been followed, normal users will not be given permission to interactively log onto security-critical machines such as domain controllers, print/file servers, ERP servers, web servers, and so forth. Affected Software Versions ========================== - Microsoft Windows NT 4.0 Workstation - Microsoft Windows NT 4.0 Server - Microsoft Windows NT 4.0 Server, Enterprise Edition - Microsoft Windows NT 4.0 Server, Terminal Server Edition - Microsoft Windows 2000 Professional - Microsoft Windows 2000 Server - Microsoft Windows 2000 Advanced Server Patch Availability ================== - Microsoft Windows NT 4.0 Workstation, Windows NT 4.0 Server, and Windows NT 4.0 Server, Enterprise Edition: http://www.microsoft.com/Downloads/Release.asp?ReleaseID=23360 - Microsoft Windows NT 4.0 Server, Terminal Server Edition patches will be available soon. - Microsoft Windows 2000 Professional, Server, and Advanced Server: http://www.microsoft.com/Downloads/Release.asp?ReleaseID=23359 Note: Additional security patches are available at the Microsoft Download Center More Information ================ Please see the following references for more information related to this issue. - Frequently Asked Questions: Microsoft Security Bulletin MS00-052, http://www.microsoft.com/technet/security/bulletin/fq00-052.asp - Microsoft Knowledge Base (KB) article Q269049, http://www.microsoft.com/technet/support/kb.asp?ID=269049 - Microsoft TechNet Security web site, http://www.microsoft.com/technet/security/default.asp Obtaining Support on this Issue =============================== This is a fully supported patch. Information on contacting Microsoft Product Support Services is available at http://support.microsoft.com/support/contact/default.asp. Revisions ========= - July 28, 2000: Bulletin Created. - ------------------------------------------------------------- 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. Last Updated July 28, 2000 (c) 2000 Microsoft Corporation. All rights reserved. Terms of use. -----BEGIN PGP SIGNATURE----- Version: PGP Personal Privacy 6.5.3 iQEVAwUBOYIp940ZSRQxA/UrAQHEFgf+JIkOAuWh1OnXbn5F2ZFVOnzUC8HA6bx0 iq6hgXbaJketxqtGEM62RgP0wnNBxFAhoOVnzSqFWjp9rPFG5oZOTeKqBcGxQOQr Hxqnz/ZVyXdJbBx1fu2nfoKTklE4x+8RGegATgKm42zJNf6mC+GOJSyUtIRXjuxc e3ppMrbqxvUiV10xHWuc3sPVIdpTEuRNIJfq/dr0cQQufb3dgHt5RNbtuhvAcS/Z s29lFQspNkwCFVArMle+7USU/ZKEpYdPnEagC393TMVcVGVmm5dEn4Ioqrio32kO 8oGFO5/5XT7sDTvpXZ5/Of27Yf3OE+IQ1wiQA2dbw8FhW8G5SL6CMQ== =eyvg -----END PGP SIGNATURE----- ******************************************************************* You have received this e-mail bulletin as a result of your registration to the Microsoft Product Security Notification Service. 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