Microsoft Word Vulnerability

Systems Affected

• Microsoft Word 2003
• Microsoft Word XP (2002)

Microsoft Word is included in Microsoft Works Suite and Microsoft Office. Other versions of Word, and other Office programs may be affected or act as attack vectors.

Overview

A buffer overflow vulnerability in Microsoft Word could allow an attacker to execute arbitrary code on a vulnerable system.

I. Description

Microsoft Word contains a buffer overflow vulnerability. Opening a specially crafted Word document, including documents hosted on web sites or attached to email messages, could trigger the vulnerability.

Office documents can contain embedded objects. For example, a malicious Word document could be embedded in an Excel or PowerPoint document. Office documents other than Word documents could be used as attack vectors.

For more information, please see Vulnerability Note VU#446012.

II. Impact

By convincing a user to open a specially crafted Word document, an attacker could execute arbitrary code on a vulnerable system. If the user has administrative privileges, the attacker could gain complete control of the system.

III. Solution

Do not open untrusted Word documents

Do not open unfamiliar or unexpected Word or other Office documents, including those received as email attachments or hosted on a web site. Please see Cyber Security Tip ST04-010 for more information.

Do not rely on file extension filtering

In most cases, Windows will call Word to open a document even if the document has an unknown file extension. For example, if document.d0c (note the digit "0") contains the correct file header information, Windows will open document.d0c with Word.

Appendix A. References

• Vulnerability Note VU#446012 - <http://www.kb.cert.org/vuls/id/446012>
• Cyber Security Tip ST04-010 - <http://www.us-cert.gov/cas/tips/ST04-010.html>

Information used in this document came from SANS and Microsoft.

Feedback can be directed to US-CERT.

Produced 2006 by US-CERT, a government organization. Terms of use

Revision History

May 19, 2006: Initial release