The image upload feature in Tiki CMS/Groupware (TikiWiki) 1.8.1 and earlier allows remote attackers to upload and possibly execute arbitrary files via the img/wiki_up URL.
https://exchange.xforce.ibmcloud.com/vulnerabilities/15849
https://euvd.enisa.europa.eu/vulnerability/EUVD-2004-1921
http://www.securityfocus.com/bid/10100
http://tikiwiki.org/tiki-read_article.php?articleId=66