iDefense Security Advisory 08.10.10 http://labs.idefense.com/intelligence/vulnerabilities/ Aug 10, 2010 I. BACKGROUND Microsoft Word is a word processing application from Microsoft Office. For more information about Microsoft Word, see the following website: http://office.microsoft.com/en-us/word/default.aspx Rich-Text Format (RTF) is a document file format developed by Microsoft for cross-platform document interchange. II. DESCRIPTION Remote exploitation of a heap buffer overflow vulnerability in Microsoft Corp.'s Word could allow attackers to execute arbitrary code under the privileges of the targeted user. This vulnerability specifically exists in the handling of some drawing object control words in an RTF document. Under certain circumstances, Word will copy a property value into a heap buffer without checking the length, which causes a heap buffer overflow. III. ANALYSIS Exploitation allows remote attackers to execute arbitrary code on the affected host under the context of the user who opened the malicious RTF document with Microsoft Word. Exploitation might require that the user open a specially crafted RTF document with a vulnerable application. The most likely exploitation vector involves convincing a user to open an RTF document sent to the user via e-mail or linked on a website. IV. DETECTION iDefense has confirmed the existence of this vulnerability in Microsoft Word 2003, Microsoft Word 2007, and Microsoft Outlook 2007. A full list of vulnerable Microsoft products can be found in Microsoft Security Bulletin MS10-056. V. WORKAROUND Microsoft suggested workarounds can be found in Microsoft Security Bulletin MS10-056. VI. VENDOR RESPONSE Microsoft Corp. has released patches which address this issue. Information about downloadable vendor updates can be found by clicking on the URLs shown. http://www.microsoft.com/technet/security/bulletin/MS10-056.mspx VII. CVE INFORMATION The Common Vulnerabilities and Exposures (CVE) project has assigned the name CVE-2010-1902 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 08/12/2009 Initial Vendor Notification 08/12/2009 Initial Vendor Reply 08/10/2010 Coordinated Public Disclosure IX. CREDIT This vulnerability was reported to iDefense by wushi of team509. 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 © 2010 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.