Integer signedness error 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 an XLS file with a large record size aka \Excel Heap Overflow Vulnerability.\