Dragging of content from different domains across windows must be disallowed (Internet zone).
This policy setting allows you to set options for dragging content from one domain to a different domain when the source and destination are in different windows. If you enable this policy setting, users can drag content from one domain to a different domain when the source and destination are in different windows. Users cannot change this setting. If you disable this policy setting, users cannot drag content from one domain to a different domain when both the source and destination are in different windows. Users cannot change this setting. If you do not configure this policy setting, users cannot drag content from one domain to a different domain when the source and destination are in different windows. Users can change this setting in the Internet Options dialog.
How this relates to the STIG checklist: STIG vs SCAP benchmark.