SQL injection vulnerability in admin/login.php in Chipmunk Guestbook allows remote attackers to execute arbitrary SQL commands and bypass login authentication via the User name.
https://exchange.xforce.ibmcloud.com/vulnerabilities/25695
http://www.vupen.com/english/advisories/2006/1323
http://www.securityfocus.com/bid/17483
http://www.securityfocus.com/archive/1/430315/100/0/threaded