Integer underflow in Microsoft Excel 2002 SP3 2003 SP3 2007 SP2 and 2010; Office 2004 and 2008 for Mac; Open XML File Format Converter for Mac; Excel Viewer SP2; and Office Compatibility Pack for Word Excel and PowerPoint 2007 File Formats SP2 allows remote attackers to execute arbitrary code via a crafted 400h substream in an Excel file which triggers a stack-based buffer overflow aka \Excel Integer Overrun Vulnerability.\