Microsoft Internet Explorer 5.01 SP4 and 6 SP1 does not properly validate parameters during calls to navigation methods, which allows remote attackers to execute arbitrary code via a crafted HTML document that triggers memory corruption, aka "Parameter Validation Memory Corruption Vulnerability."
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A5231
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2008/ms08-073
http://www.vupen.com/english/advisories/2008/3385