home/register.php in Eggblog before 3.0 allows remote attackers to change the password of administrators and possibly other users via a modified username parameter.
https://exchange.xforce.ibmcloud.com/vulnerabilities/26833
http://www.securityfocus.com/archive/1/435300/100/0/threaded
http://www.securityfocus.com/archive/1/435284/100/0/threaded