If you haven't hit the Windows Update button yet today, you should. Microsoft today released 14 patches to plug security holes in several versions of its Windows operating system, Internet Explorer Web browser, Excel and other programs. Six of these updates are rated critical by Microsoft, meaning that attackers could exploit the flaws with no user action required. The other three updates are rated important.

MS07-042 - Vulnerability in Microsoft XML Core Services Could Allow Remote Code Execution (936227)
MS07-043 - Vulnerability in OLE Automation Could Allow Remote Code Execution (921503)
MS07-044 - Vulnerability in Microsoft Excel Could Allow Remote Code Execution (940965)
MS07-045 - Cumulative Security Update for Internet Explorer (937143)
MS07-046 - Vulnerability in GDI Could Allow Remote Code Execution (938829)
MS07-047 - Vulnerability in Windows Media Player Could Allow Remote Code Execution (936782)
MS07-048 - Vulnerabilities in Windows Gadgets Could Allow Remote Code Execution (938123)
MS07-049 - Vulnerability in Virtual PC and Virtual Server Could Allow Elevation of Privilege (937986)
MS07-050 - Vulnerability in Vector Markup Language Could Allow Remote Code Execution (938127)

Most important is the MS07-046 update, which fixes a critical flaw in the graphics rendering system used by Windows. The flaw lies in the Windows graphics device interface (GDI) software used to send graphics data to printers and monitors. Microsoft says that attackers could exploit this flaw by tricking a victim into opening a specially crafted e-mail attachment, but because the bug lies in a core component of Windows. The flaw affects all supported versions of Windows, except Windows Vista and Windows Server 2003 Service pack 2.