Directory traversal vulnerability in admin/includes/languages/english.php in Zen Cart 1.3.8a, 1.3.8, and earlier, when .htaccess is not supported, allows remote attackers to include and execute arbitrary local files via a .. (dot dot) in the _SESSION[language] parameter. NOTE: the vendor disputes this issue, stating "at worst, the use of this vulnerability will reveal some local file paths.
https://www.exploit-db.com/exploits/6038
https://euvd.enisa.europa.eu/vulnerability/EUVD-2008-6838
http://www.zen-cart.com/forum/showthread.php?t=102802
http://www.securityfocus.com/bid/30179
http://www.attrition.org/pipermail/vim/2008-July/002028.html