noVNC before 0.5 does not set the secure flag for a cookie in an https session, which makes it easier for remote attackers to capture this cookie by intercepting its transmission within an http session.
rhn.redhat.com/errata/RHSA-2015-0788.html
rhn.redhat.com/errata/RHSA-2015-0833.html
rhn.redhat.com/errata/RHSA-2015-0834.html
rhn.redhat.com/errata/RHSA-2015-0884.html
www.openwall.com/lists/oss-security/2015/02/17/1
www.openwall.com/lists/oss-security/2015/03/12/13
bugzilla.redhat.com/show_bug.cgi?id=1193451
github.com/kanaka/noVNC/commit/ad941faddead705cd611921730054767a0b32dcd