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 integer overflow 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 when handling CString objects embedded in a PowerPoint presentation file. An issue in this object results in a very small amount of buffer being allocated while a very large amount of data is copied into it. This leads to an exploitable heap-based buffer overflow. III. ANALYSIS Exploitation allows an attacker to execute arbitrary code in the context of a user opening a malicious presentation using Microsoft PowerPoint Viewer 2003. In order to exploit this vulnerability, an attacker must persuade, or otherwise force, a targeted user to open such a document. This could be accomplished using a direct URL, an e-mail, an instant message, or even by hijacking a trusted site. IV. DETECTION iDefense has confirmed that pptview.exe file version 11.0.5703.0 and file version 11.0.6566.0, as included in Microsoft Office 2003 SP2, are vulnerable. Other versions are also likely to be affected. Version 11.0.8164.0 of pptview.exe, as included in Microsoft Office 2003 SP3, does not appear to be 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-2008-0120 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. Get paid for vulnerability research http://labs.idefense.com/methodology/vulnerability/vcp.php Free tools, research and upcoming events http://labs.idefense.com/ X. LEGAL NOTICES Copyright © 2008 iDefense, Inc. Permission is granted for the redistribution of this alert electronically. It may not be edited in any way without the express written consent of iDefense. If you wish to reprint the whole or any part of this alert in any other medium other than electronically, please e-mail customerservice@idefense.com for permission. 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 author nor the publisher accepts any liability for any direct, indirect, or consequential loss or damage arising from use of, or reliance on, this information. _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/