Disabling cross domain drag and drop functionality can help avoid attacks where a malicious site may trick you into unknowingly selecting possibly sensitive content from one website and dropping the content into a possibly malicious website.

You can automatically disable this if you haven’t already got the appropriate patches (read more) with the following Microsoft Fixit:
Microsoft Fixit 50743

Read more at the KB article (2581921)

How to prevent cross-domain drag-and-drop functionality in Internet Explorer

Get More help for Internet Explorer