Microsoft Office Excel 2007 SP1 and SP2; Office 2008 for Mac; Open XML File Format Converter for Mac; Office Excel Viewer SP1 and SP2; Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP1 and SP2; and Office SharePoint Server 2007 SP1 and SP2 do not validate ZIP headers during decompression of Open XML (.XLSX) documents, which allows remote attackers to execute arbitrary code via a crafted document that triggers access to uninitialized memory locations, aka "Microsoft Office Excel XLSX File Parsing Code Execution Vulnerability."