Cross-site scripting (XSS) vulnerability in index.php in ExpressionEngine 1.2.1 and earlier allows remote attackers to inject arbitrary web script or HTML via the URL parameter.
https://exchange.xforce.ibmcloud.com/vulnerabilities/39442
http://www.securityfocus.com/bid/27128
http://www.securityfocus.com/archive/1/485786/100/0/threaded
http://websecurity.com.ua/1454/