Home page logo
/

bugtraq logo Bugtraq mailing list archives

Microsoft Security Bulletin (MS99-050)
From: aleph1 () UNDERGROUND ORG (Aleph One)
Date: Thu, 9 Dec 1999 17:34:52 -0800


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 (MS99-050)
--------------------------------------

Patch Available for "Server-side Page Reference Redirect" Vulnerability
Originally Posted: December 08, 1999

Summary
=======
Microsoft has released a patch that eliminates a vulnerability in
Microsoft(r) Internet Explorer  4.01, 5 and 5.01, that could allow a
malicious web site operator to view a file on the computer  of a visiting
user, provided that the web site operator knew the name and folder of the
file.

Frequently asked questions regarding this vulnerability can be found at
http://www.microsoft.com/security/bulletins/MS99-050faq.asp.

Issue
=====
When a web server performs a server-side redirect, the IE security model
checks the server's  permissions on the new page. However, under favorable
timing conditions, it is possible for a web  server to create a reference to
a client window that the server is permitted to view, then use a
server-side redirect to a client-local file, and bypass the security
restrictions. The result is  that it could be possible for a malicious web
site operator to view files on the computer of a  visiting user. The web
site operator would need to know (or guess) the name and location of the
file.

Affected Software Versions
==========================
 - Microsoft Internet Explorer 4.01
 - Microsoft Internet Explorer 5.0
 - Microsoft Internet Explorer 5.01

Patch Availability
==================
 - http://www.microsoft.com/windows/ie/security/servredir.asp

NOTE: This patch also includes the previously-released patch for the
"ImportExportFavorites"  vulnerability.

NOTE: This and other patches are available from the Microsoft
Download Center (http://www.microsoft.com/downloads/search.asp?
Search=Keyword&Value='security_patch'&OpSysID=1)

NOTE: Microsoft produces security patches for Internet Explorer 4.01 SP2 and
higher. In the event  that this package is applied to Internet Explorer 4.01
SP1, the package states that a fix is not  needed. This message is
incorrect, as the vulnerability does exist on Internet Explorer 4.01 SP1  or
any earlier release. If you are using Internet Explorer 4.01 SP1 or any
earlier release,  please upgrade to the latest version of Internet Explorer
to resolve this issue.

NOTE: The patch will be available shortly at the WindowsUpdate site. When
this happens, we will  modify the bulletin to provide additional
information.

More Information
================
Please see the following references for more information related to this
issue.
 - Microsoft Security Bulletin MS99-050: Frequently Asked Questions,
   http://www.microsoft.com/security/bulletins/MS99-050faq.asp.
 - Microsoft Knowledge Base (KB) article Q246094,
   Update Available for "Server-side Page Reference Redirect"
   Vulnerability,
   http://support.microsoft.com/support/kb/articles/q246/0/94.asp.
   (NOTE: It may take 24 hours from the original posting of this bulletin
   for this 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.

Revisions
=========
 - December 08, 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.


  By Date           By Thread  

Current thread:
  • Microsoft Security Bulletin (MS99-050) Aleph One (Dec 10)
[ Nmap | Sec Tools | Mailing Lists | Site News | About/Contact | Advertising | Privacy ]