z3c.form in Plone CMS 5.x through 5.0.6 and 4.x through 4.3.11 allows remote attackers to conduct cross-site scripting (XSS) attacks via a crafted GET request.
packetstormsecurity.com/files/139110/Plone-CMS-4.3.11-5.0.6-XSS-Traversal-Open-Redirection.html
seclists.org/fulldisclosure/2016/Oct/80
www.openwall.com/lists/oss-security/2016/09/05/4
www.openwall.com/lists/oss-security/2016/09/05/5
www.securityfocus.com/archive/1/539572/100/0/threaded
www.securityfocus.com/bid/92752
plone.org/security/hotfix/20160830/non-persistent-xss-in-plone-forms