From secnotif@MICROSOFT.COM Fri Sep 10 14:28:09 1999 From: Microsoft Product Security Resent-From: mea culpa To: MICROSOFT_SECURITY@ANNOUNCE.MICROSOFT.COM Resent-To: jericho@attrition.org Date: Thu, 9 Sep 1999 21:14:20 -0700 Subject: Microsoft Security Bulletin (MS99-033) 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. ******************************** Microsoft Security Bulletin (MS99-033) -------------------------------------- Patch Available for "Malformed Telnet Argument" Vulnerability Originally Posted: September 09, 1999 Summary ======= Microsoft has released a patch that eliminates a vulnerability in the Telnet client that ships as part of Microsoft(r) Windows(r) 95 and 98. The vulnerability could allow arbitrary code to be executed on the user's computer. Frequently asked questions regarding this vulnerability can be found at http://www.microsoft.com/security/bulletins/MS99-033faq.asp Issue ===== The Telnet client that ships as part of Windows 95 and 98 has an unchecked buffer. A specially-malformed argument could be passed to the client via a web page in order to cause arbitrary code to execute on the computer via a classic buffer overrun technique. Affected Software Versions ========================== - Microsoft Windows 95 - Microsoft Windows 98 - Microsoft Windows 98 Second Edition Patch Availability ================== - Microsoft Windows 95 http://www.microsoft.com/windows95/downloads/contents/ WUCritical/Telnet/Default.asp - Microsoft Windows 98 and Windows 98 Second Edition http://www.microsoft.com/windows98/downloads/contents/ WUCritical/Telnet/Default.asp NOTE: Line breaks have been inserted into the above URLs for readability NOTE: This patch also will be available via WindowsUpdate (www.microsoft.com/windowsupdate) circa September 10, 1999. More Information ================ Please see the following references for more information related to this issue. - Microsoft Security Bulletin MS99-033: Frequently Asked Questions, http://www.microsoft.com/security/bulletins/MS99-033faq.asp. - Microsoft Knowledge Base (KB) article Q240163, Buffer Overrun in Telnet in Windows 98 Poses a Security Risk, http://support.microsoft.com/support/kb/articles/q240/1/63.asp. (Note: It may take 24 hours from the original posting of this bulletin for the KB article to be visible.) - Microsoft Security Advisor web site, http://www.microsoft.com/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. Acknowledgments =============== Microsoft acknowledges Jeremy Kothe for bringing this issue to our attention. Revisions ========= - September 09, 1999: 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. (c) 1999 Microsoft Corporation. All rights reserved. Terms of Use. ******************************************************************* You have received this e-mail bulletin as a result of your registration to the Microsoft Product Security Notification Service. You may unsubscribe from this e-mail notification service at any time by sending an e-mail to MICROSOFT_SECURITY-SIGNOFF-REQUEST@ANNOUNCE.MICROSOFT.COM The subject line and message body are not used in processing the request, and can be anything you like. For more information on the Microsoft Security Notification Service please visit http://www.microsoft.com/security/services/bulletin.asp. For security-related information about Microsoft products, please visit the Microsoft Security Advisor web site at http://www.microsoft.com/security.