Microsoft is investigating a new report of limited zero-day attacks using a vulnerability in Microsoft Word 2000, Microsoft Word 2002, Microsoft Office Word 2003, Microsoft Word Viewer 2003, Microsoft Word 2004 for Mac, and Microsoft Word 2004 v. X for Mac, as well as Microsoft Works 2004, 2005, and 2006.

In order for this attack to be carried out, a user must first open a malicious Word file attached to an e-mail or otherwise provided to them by an attacker.

Customers in the U.S. and Canada who believe they are affected can receive technical support from Microsoft Product Support Services at 1-866-PCSAFETY. There is no charge for support calls that are associated with security updates.

International customers can receive support from their local Microsoft subsidiaries. For more information about how to contact Microsoft for support issues, visit the International Support Web site.