This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Microsoft Internet Explorer. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.
The vulnerability relates to how Internet Explorer handles CSS generated content. By performing certain manipulations on the elements of a document that includes CSS generated content, an attacker can force a CGeneratedTreeNode object in memory to be reused after it has been freed. An attacker can leverage this vulnerability to execute code under the context of the current process.