Mozilla Firefox before 49.0 allows user-assisted remote attackers to obtain sensitive full-pathname information during a local-file drag-and-drop operation via crafted JavaScript code.
https://security.gentoo.org/glsa/201701-15
https://bugzilla.mozilla.org/show_bug.cgi?id=1249522
http://www.securitytracker.com/id/1036852
http://www.securityfocus.com/bid/93052
http://www.mozilla.org/security/announce/2016/mfsa2016-85.html