The toStaticHTML function in Microsoft Internet Explorer 8, and the SafeHTML function in Microsoft Windows SharePoint Services 3.0 SP2, SharePoint Foundation 2010, Office SharePoint Server 2007 SP2, Groove Server 2010, and Office Web Apps, allows remote attackers to bypass the cross-site scripting (XSS) protection mechanism and conduct XSS attacks via a crafted use of the Cascading Style Sheets (CSS) @import rule, aka "HTML Sanitization Vulnerability," a different vulnerability than CVE-2010-1257.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A7297
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2010/ms10-072
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2010/ms10-071