The tblinf32.dll (aka vstlbinf.dll) ActiveX control for Internet Explorer 5.01, 6 SP1, and 7 uses an incorrect IObjectsafety implementation, which allows remote attackers to execute arbitrary code by requesting the HelpString property, involving a crafted DLL file argument to the TypeLibInfoFromFile function, which overwrites the HelpStringDll property to call the DLLGetDocumentation function in another DLL file, aka "ActiveX Object Vulnerability."
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A2109
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2007/ms07-045
http://www.vupen.com/english/advisories/2007/2869
http://www.us-cert.gov/cas/techalerts/TA07-226A.html
http://www.securityfocus.com/bid/25289
http://www.securityfocus.com/archive/1/476742/100/0/threaded