Multiple cross-site scripting (XSS) vulnerabilities in TWiki before 5.1.0 allow remote attackers to inject arbitrary web script or HTML via (1) the newtopic parameter in a WebCreateNewTopic action, related to the TWiki.WebCreateNewTopicTemplate topic; or (2) the query string to SlideShow.pm in the SlideShowPlugin.
http://www.securityfocus.com/bid/49746
http://www.mavitunasecurity.com/xss-vulnerability-in-twiki5
http://twiki.org/cgi-bin/view/Codev/SecurityAlert-CVE-2011-3010
http://securitytracker.com/id?1026091
http://secunia.com/advisories/46123
http://develop.twiki.org/trac/changeset/21920
http://archives.neohapsis.com/archives/bugtraq/2011-09/0142.html