phpCommunityCalendar is prone to multiple SQL injection vulnerabilities. These issues are due to a lack of proper sanitization of user-supplied input before being used in SQL queries.
Successful exploitation could result in a compromise of the application, disclosure or modification of data, or may permit an attacker to exploit vulnerabilities in the underlying database implementation.
http://www.example.com/[path]/webadmin/login.php and use this:
login: ' or isnull(1/0) /*
password: [nothing here]