From secnotif@MICROSOFT.COM Fri Jun 16 02:17:27 2000 From: Microsoft Product Security Resent-From: mea culpa To: MICROSOFT_SECURITY@ANNOUNCE.MICROSOFT.COM Resent-To: jericho@attrition.org Date: Thu, 15 Jun 2000 12:12:28 -0700 Subject: Microsoft Security Bulletin (MS00-020) 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 (MS00-020) - -------------------------------------- Patch Available for "Desktop Separation" Vulnerability Originally Posted: June 15, 2000 Summary ======= Microsoft has released a patch that eliminates a security vulnerability in Microsoft(r) Windows(r) 2000. The vulnerability could allow a malicious user to gain additional privileges on a machine that he could log onto at the keyboard. Frequently asked questions regarding this vulnerability can be found at http://www.microsoft.com/technet/security/bulletin/fq00-020.asp. Issue ===== In the Windows 2000 security model, a hierarchy of container objects is used to separate processes. Every session contains one or more windows stations; every windows station contains one or more desktops. By design, processes are constrained to run within a windows station, and the threads in the process run in one or more desktops. A process in one windows station should not be able to access desktops belonging to another windows station. However, due to an implementation error, this could happen under very specific circumstances. This could allow a process belonging to a low-privilege user to view inputs or output that belong to another desktop within the same session, and potentially obtain information such as passwords. The vulnerability only affects desktops within the same session. As a result, a malicious user could only interfere with processes on the same local machine, and only if he could interactively log onto it. Security best practices strongly militate against allowing normal users to interactively log onto security-sensitive servers, and if this practice has been followed, machines such as domain controllers, print and file servers, ERP servers, database servers, and others would not be at risk. In addition, other security best practices, if followed, would prevent a malicious user from launching the processes in a way that allows them to exploit this vulnerability. Windows 2000 Terminal Servers are not affected by this vulnerability, because every user runs in his own session. Affected Software Versions ========================== - Microsoft Windows 2000 Professional - Microsoft Windows 2000 Server - Microsoft Windows 2000 Advanced Server Patch Availability ================== - http://www.microsoft.com/Downloads/Release.asp?ReleaseID=20836 Note: Due to a known compatibility error, the patch should not be applied to clustered Windows 2000 systems that are administered via the Microsoft Management Console. 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. - Microsoft Security Bulletin MS00-020: Frequently Asked Questions, http://www.microsoft.com/technet/security/bulletin/fq00-020.asp - Microsoft Knowledge Base (KB) article Q260197 discusses this issue and will be available soon. - 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 Technical Support is available at http://support.microsoft.com/support/contact/default.asp Revisions ========= - June 15, 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 June 15, 2000 (c) 2000 Microsoft Corporation. All rights reserved. Terms of use. -----BEGIN PGP SIGNATURE----- Version: PGP 6.0.2 iQEVAwUBOUkqnY0ZSRQxA/UrAQHIDAf/XQb8N2Te7N77CtUFB0ycyqL2nFuI2DN4 fPwD+egcb7bTbuPds5BfuvDWpLdLkwHr17UrWKFRaYRB41Ul8VAizW/W1JNwuNwi TgncN99oPRt+Dn9yHRR3zygUkf7NfzVxZrN22Xv+AQPt6VDdV7HiZPOLt1wimvsk 6D7+CXM5uUKXqDwHQYRdqMT4hL7NqlRTk+QZ32GFuitrilOM/aQX8eIAy8HPYoz5 TXl9KUHEt2j4YI/ktA1lR36lzJs/Wzm4YPu+XJyr/b7bPzb7K/vuQ3Q85ROyyP/I 0Ej/gFLa9spWVVH/zx3kxYJghhTp+UDyfvq4bmJM14S8VCWwW+jZFQ== =hDg+ -----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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