tiki-graph_formula.php in TikiWiki 1.9.8 allows remote attackers to execute arbitrary code via PHP sequences in the f array parameter, which are processed by create_function.
https://www.exploit-db.com/exploits/4509
https://exchange.xforce.ibmcloud.com/vulnerabilities/37076
http://www.vupen.com/english/advisories/2007/3492
http://www.securityfocus.com/archive/1/482128/100/0/threaded
http://www.securityfocus.com/archive/1/482006/100/0/threaded
http://www.gentoo.org/security/en/glsa/glsa-200710-21.xml
http://sourceforge.net/project/shownotes.php?release_id=546283&group_id=64258
http://sourceforge.net/forum/forum.php?forum_id=744898
http://securityreason.com/securityalert/3216
http://secunia.com/advisories/27344