Microsoft Excel 2002 SP3 allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crafted RealTimeData record, related to a stTopic field, double-byte characters, and an incorrect pointer calculation, aka "Excel Record Parsing WriteAV Vulnerability."
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2011/ms11-021
http://secunia.com/advisories/39122
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11676
http://www.securitytracker.com/id?1025337
http://www.us-cert.gov/cas/techalerts/TA11-102A.html