Public Vulnerability Reports

Microsoft Word RTF File Parsing Stack Buffer Overflow Vulnerability

11.09.10

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.

DESCRIPTION

Remote exploitation of a stack 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 a specific control word in an RTF document. Under certain circumstances, Word will copy its property strings into a stack buffer without checking the length, which causes a stack buffer overflow.

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.

Since Outlook 2007 uses the Word engine to process e-mails, it is also affected by this vulnerability. The attacker can send the user a specially crafted RTF e-mail. When this e-mail is opened or displayed in the preview pane using Outlook 2007, the vulnerability will be triggered.

DETECTION

iDefense has confirmed the existence of this vulnerability in Microsoft Word 2003, Microsoft Word 2007, and Microsoft Outlook 2007. The following Microsoft products are vulnerable:

 * Microsoft Office XP SP 3 * Microsoft Office 2003 SP 3 * Microsoft Office 2007 SP 2 * Microsoft Office 2010 (32-bit editions) * Microsoft Office 2010 (64-bit editions) * Microsoft Office for Mac 2011 

WORKAROUND

Microsoft recommends reading e-mail in plain-text format as a workaround.

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/MS10-087.mspx

CVE INFORMATION

The Common Vulnerabilities and Exposures (CVE) project has assigned the name CVE-2010-3333 to this issue. This is a candidate for inclusion in the CVE list (http://cve.mitre.org/), which standardizes names for security problems.

DISCLOSURE TIMELINE

08/12/2009 Initial Vendor Notification
08/12/2009 Initial Vendor Reply
11/09/2010 Coordinated Public Disclosure

CREDIT

This vulnerability was reported to iDefense by wushi of team509.

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LEGAL NOTICES

Copyright © 2010 Verisign, Inc.

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