Microsoft Internet Explorer 8 and earlier, and Internet Explorer 9 beta, does not properly restrict cross-zone drag-and-drop actions, which allows user-assisted remote attackers to read cookie files via vectors involving an IFRAME element with a SRC attribute containing a file: URL, as demonstrated by a Facebook game, related to a "cookiejacking" issue.

Microsoft Internet Explorer 6 through 9, and 10 Consumer Preview, allows remote attackers to bypass Protected Mode or cause a denial of service (memory corruption) by leveraging access to a Low integrity process, as demonstrated by VUPEN during a Pwn2Own competition at CanSecWest 2012.

The setRequestHeader method of the XMLHttpRequest object in Microsoft Internet Explorer 7 does not restrict the dangerous Transfer-Encoding HTTP request header, which allows remote attackers to conduct HTTP request splitting and HTTP request smuggling attacks via a POST containing a "Transfer-Encoding: chunked" header and a request body with an incorrect chunk size.

Stack-based buffer overflow in the AddFavorite method in Microsoft Internet Explorer allows remote attackers to cause a denial of service (application crash) and possibly have unspecified other impact via a long URL in the first argument.