iDefense Security Advisory 08.12.08
http://labs.idefense.com/intelligence/vulnerabilities/
Aug 12, 2008

I. BACKGROUND

Microsoft Corp.'s PowerPoint Viewer is a viewer for full-featured
presentations created in PowerPoint 97 and later versions. PowerPoint
Viewer 2003 is freely downloadable from Microsoft's website at the
following URL.

http://www.microsoft.com/downloads/details.aspx?FamilyId=428D5727-43AB-4F24-90B7-A94784AF71A4

II. DESCRIPTION

Remote exploitation of an out of boundary array index vulnerability in
Microsoft Corp.'s PowerPoint Viewer 2003 could allow an attacker to
execute arbitrary code in the context of the user running the
application.

This vulnerability specifically exists in PowerPoint Viewer 2003 when
handling certain records in a PowerPoint presentation file. In some
circumstances, an array index can be directly controlled by data from
within the PowerPoint presentation file. Thus, a function pointer can
be directly controlled by the attacker and leveraged for arbitrary code
execution.

III. ANALYSIS

Exploitation allows an attacker to execute arbitrary code on the
affected host in the context of the user who opened a malicious PPT
presentation using Microsoft PowerPoint Viewer 2003.

Exploitation of this vulnerability would require an attacker to either
host a malicious PowerPoint presentation file and use social
engineering techniques to trick a user into visiting the site or to
deliver the hostile code to a user via e-mail, for example. The user
would then need to view the file using Microsoft's PowerPoint Viewer.

IV. DETECTION

iDefense has confirmed that pptview.exe file version 11.0.5703.0 is
vulnerable. Previous versions are also likely to be affected.

pptview.exe file version 11.0.6566.0, as included in Microsoft Office
2003 SP2, and version 11.0.8164.0, as included in Microsoft Office 2003
SP3 appear to be not affected.

V. WORKAROUND

iDefense is currently unaware of any effective workaround for this
issue.

VI. VENDOR RESPONSE

Microsoft has officially addressed this vulnerability with Security
Bulletin MS08-051. For more information, consult their bulletin at the
following URL.

http://www.microsoft.com/technet/security/bulletin/ms08-051.mspx

VII. CVE INFORMATION

The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CVE-2008-0121 to this issue. This is a candidate for inclusion in
the CVE list (http://cve.mitre.org/), which standardizes names for
security problems.

VIII. DISCLOSURE TIMELINE

09/28/2007  Initial vendor notification
09/28/2007  Initial vendor response
08/12/2008  Coordinated public disclosure

IX. CREDIT

This vulnerability was reported to iDefense by Ruben Santamarta from
Reversemode.com.

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X. LEGAL NOTICES

Copyright © 2008 iDefense, Inc.

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Disclaimer: The information in the advisory is believed to be accurate
at the time of publishing based on currently available information. Use
of the information constitutes acceptance for use in an AS IS condition.
 There are no warranties with regard to this information. Neither the
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