The remote web server contains a script that is vulnerable to a SQL injection attack.
The remote host is running WebCalendar, a web-based calendar management program. This version of WebCalendar is vulnerable to a SQL injection attack via the user_valid_crypt parameter of the users.php script. An attacker exploiting this flaw would be able to read/modify data or execute commands as the web server process.
Upgrade to version 1.0.0 or higher.