Microsoft Excel 2002 SP3, Office 2008 for Mac, and Open XML File Format Converter for Mac do not properly validate record information during parsing of Excel spreadsheets, which allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crafted spreadsheet, aka "Excel Memory Corruption Vulnerability."
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A12291
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2011/ms11-045