Session fixation vulnerability in Zen Cart 1.3.7 and earlier allows remote attackers to hijack web sessions by setting the Cookie parameter.
http://www.securityfocus.com/archive/1/472875/100/0/threaded
http://superb-east.dl.sourceforge.net/sourceforge/zencart/zen-cart-v1.3.7-admin-patch.zip
http://sourceforge.net/project/shownotes.php?release_id=474574&group_id=83781
http://securityreason.com/securityalert/2866