Microsoft Internet Explorer 6, 7, and 8 does not enforce intended domain restrictions on content access, which allows remote attackers to obtain sensitive information or conduct clickjacking attacks via a crafted web site, aka "Frame Tag Information Disclosure Vulnerability."
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11926
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2011/ms11-018