The django.util.http.is_safe_url function in Django before 1.4.18, 1.6.x before 1.6.10, and 1.7.x before 1.7.3 does not properly handle leading whitespaces, which allows remote attackers to conduct cross-site scripting (XSS) attacks via a crafted URL, related to redirect URLs, as demonstrated by a "\njavascript:" URL.
http://www.mandriva.com/security/advisories?name=MDVSA-2015:109
http://www.mandriva.com/security/advisories?name=MDVSA-2015:036
http://ubuntu.com/usn/usn-2469-1
http://secunia.com/advisories/62718
http://secunia.com/advisories/62309
http://secunia.com/advisories/62285
http://lists.opensuse.org/opensuse-updates/2015-09/msg00035.html
http://lists.opensuse.org/opensuse-updates/2015-04/msg00001.html
http://lists.fedoraproject.org/pipermail/package-announce/2015-January/148608.html
http://lists.fedoraproject.org/pipermail/package-announce/2015-January/148485.html