Session fixation vulnerability in chameleon cms 3.0 and earlier allows remote attackers to hijack web sessions by setting the PHPSESSID parameter.
https://exchange.xforce.ibmcloud.com/vulnerabilities/34684
http://www.securityfocus.com/archive/1/470759/100/0/threaded
http://www.securityfocus.com/archive/1/470273/100/0/threaded
http://www.majorsecurity.de/index_2.php?major_rls=major_rls50