Alert

Critical Vulnerabilities in Microsoft Windows

Last Revised
Alert Code
TA04-212A

Systems Affected

These vulnerabilities affect the following versions of Microsoft
Internet Explorer:

  • Microsoft Internet Explorer 5.01 Service Pack 2
  • Microsoft Internet Explorer 5.01 Service Pack 3
  • Microsoft Internet Explorer 5.01 Service Pack 4
  • Microsoft Internet Explorer 5.5 Service Pack 2
  • Microsoft Internet Explorer 6
  • Microsoft Internet Explorer 6 Service Pack 1
  • Microsoft Internet Explorer 6 Service Pack 1 (64-Bit Edition)
  • Microsoft Internet Explorer 6 for Windows Server 2003
  • Microsoft Internet Explorer 6 for Windows Server 2003 (64-Bit Edition)

These vulnerabilities affect the following versions of the
Microsoft Windows operating system:

  • Microsoft Windows NT Workstation 4.0 Service Pack 6a
  • Microsoft Windows NT Server 4.0 Service Pack 6a
  • Microsoft Windows NT Server 4.0 Terminal Server Edition Service Pack 6
  • Microsoft Windows 2000 Service Pack 2, Microsoft Windows 2000 Service Pack 3, Microsoft Windows 2000 Service Pack 4
  • Microsoft Windows XP and Microsoft Windows XP Service Pack 1
  • Microsoft Windows XP 64-Bit Edition Service Pack 1
  • Microsoft Windows XP 64-Bit Edition Version 2003
  • Microsoft Windows Server 2003
  • Microsoft Windows Server 2003 64-Bit Edition
  • Microsoft Windows 98, Microsoft Windows 98 Second Edition (SE), and Microsoft Windows Millennium Edition (Me)

Please note that these vulnerabilities my affect any software that
uses the Microsoft Windows operating system to render HTML or
graphics.

Overview

Microsoft Internet Explorer contains three vulnerabilities that may
allow arbitrary code to be executed. The privileges gained by a remote
attacker depend on the software component being attacked. For example,
a user browsing to an unsafe web page using Internet Explorer could
have code executed with the same privilege as the user. These
vulnerabilities have been reported to be relatively straightforward to
exploit; even vigilant users visiting a malicious website, viewing a
malformed image, or reading an HTML-rendered email message may be
affected.

Description

Microsoft Security Bulletin MS04-025
describes three vulnerabilities in Internet Explorer; more detailed
information is available in the individual vulnerability
notes
. Note that in addition to Internet Explorer, any applications
that use the Internet Explorer HTML rendering engine to interpret HTML
documents may present additional attack vectors for these
vulnerabilities.

VU#266926 -
Microsoft Internet Explorer contains an integer overflow in the processing
of bitmap files

An integer overflow vulnerability has been discovered in the way that
Internet Explorer processes bitmap image files. This vulnerability could
allow a remote attacker to execute arbitrary code on a vulnerable system
by introducing a specially crafted bitmap file.

(Other resources: CAN-2004-0566)

VU#685364 -
Microsoft Internet Explorer contains a double-free vulnerability in the
processing of GIF files

A double-free vulnerability has been discovered in the way that
Internet Explorer processes GIF image files. When processing GIF image
files, the routine responsible for freeing memory may attempt to free the
same memory reference more than once. Deallocating the already freed
memory can lead to memory corruption, which could cause a
denial-of-service condition or potentially be leveraged by an attacker to
execute arbitrary code.

(Other resources: CAN-2003-1048)

VU#713878 -
Microsoft Internet Explorer does not properly validate source of
redirected frame Microsoft Internet Explorer does not properly display
URLs

As previously discussed in TA-163A,
Microsoft Internet Explorer does not adequately validate the security
context of a frame that has been redirected by a web server. An
attacker could exploit this vulnerability to evaluate script in
different security domains. By causing script to be evaluated in the
Local Machine Zone, the attacker could execute arbitrary code with the
privileges of the user running Internet Explorer. For a detailed
technical analysis of this vulnerability, please see VU#713878.

(Other resources: CAN-2004-0549)


Impact

Remote attackers exploiting the vulnerabilities described above may
execute arbitrary code with the privileges of the user running the
software components being attacked (e.g., Internet
Explorer). Attackers can exploit these vulnerabilities by convincing a
victim user to visit a malicious website, view a malformed image, or
read an HTML-rendered email message. No user intervention is required
beyond viewing an attacker-supplied HTML document or image. For
further details, please see the individual vulnerability
notes
.

Solution

Apply a patch from Microsoft

Apply the appropriate patch as specified by Microsoft Security
Bulletin MS04-025.
Please note that this bulletin provides a cumulative update that
replaces all previously released updates for Internet Explorer,
including those provided in MS04-004. However,
users who have applied hotfixes released after MS04-004
will need to install MS04-025. Please
see the FAQ section of Microsoft's advisory for more details.

Follow Microsoft recommendations for workarounds

Microsoft provides several workarounds for each of these vulnerabilities.
Please consult the appropriate section(s) of Microsoft Security Bulletin
MS04-025.

Appendix A. Vendor Information

This appendix contains information provided by vendors for this
advisory. As vendors report new information to US-CERT, we will update
this section and note the changes in our revision history. If a
particular vendor is not listed below, we have not received their
comments.

Microsoft

Please see Microsoft Security Bulletin MS04-025.

Appendix B. References



Feedback can be directed to the US-CERT
Technical Staff
.


Revision History

  • Jul 30, 2004: Initial release

    Last updated

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