The user_logout function in TikiWiki CMS/Groupware 4.x before 4.2 does not properly delete user login cookies, which allows remote attackers to gain access via cookie reuse.
https://exchange.xforce.ibmcloud.com/vulnerabilities/56770
http://tikiwiki.svn.sourceforge.net/viewvc/tikiwiki?view=rev&revision=25046
http://secunia.com/advisories/38896
http://info.tikiwiki.org/article86-Tiki-Announces-3-5-and-4-2-Releases