Vulnerabilities in Microsoft Excel could allow remote code exection. Here is the update page. This critical update resolves one publicly disclosed vulnerability and two privately reported vulnerabilities in addition to other security issues identified during the course of the investigation. These vulnerabilities could allow remote code execution if a user opens a specially crafted Excel file. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.This is a critical security update for supported editions of Microsoft Office 2000. For supported editions of Microsoft Office XP, Microsoft Office 2003, 2007 Microsoft Office System, this update is rated important. This update is also rated important for the Excel Viewer 2003, Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats. For more information, see the subsection, Affected and Non-Affected Software, in this section.

This security update addresses these vulnerabilities by modifying the way that Microsoft Excel handles specially crafted Excel files. For more information about the vulnerabilities, see the Frequently Asked Questions (FAQ) subsection for the specific vulnerability entry under the next section, Vulnerability Information.