Microsoft Excel 2002 SP3, 2003 SP3, and 2007 SP2; 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 do not properly validate record structures during parsing of Excel spreadsheets, which allows remote attackers to execute arbitrary code via a crafted spreadsheet, aka "Excel Insufficient Record Validation Vulnerability."
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A12139
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2011/ms11-045