The XMLHttpRequest object in Qt before 4.8.4 enables http redirection to the file scheme, which allows man-in-the-middle attackers to force the read of arbitrary local files and possibly obtain sensitive information via a file: URL to a QML application.
https://codereview.qt-project.org/#change%2C40034
https://bugzilla.redhat.com/show_bug.cgi?id=883415
http://www.ubuntu.com/usn/USN-1723-1
http://www.openwall.com/lists/oss-security/2012/12/04/8
http://secunia.com/advisories/52217
http://qt.gitorious.org/qt/qt/commit/96311def2466dd44de64d77a1c815b22fbf68f71
http://lists.qt-project.org/pipermail/announce/2012-November/000014.html
http://lists.opensuse.org/opensuse-updates/2013-01/msg00048.html
http://lists.opensuse.org/opensuse-updates/2013-01/msg00045.html
http://lists.opensuse.org/opensuse-updates/2013-01/msg00034.html