MyCMS 0.9.8 and earlier allows remote attackers to gain privileges via the admin cookie parameter, as demonstrated by a post to admin/settings.php that injects PHP code into settings.inc, which can then be executed via a direct request to index.php.
https://www.exploit-db.com/exploits/4145
https://exchange.xforce.ibmcloud.com/vulnerabilities/35254
http://www.securityfocus.com/archive/1/484111/100/100/threaded
http://www.securityfocus.com/archive/1/484064/100/100/threaded