This script is possibly vulnerable to SQL Injection attacks.
SQL injection is a vulnerability that allows an attacker to alter backend SQL statements by manipulating the user input. An SQL injection occurs when web applications accept user input that is directly placed into a SQL statement and doesn’t properly filter out dangerous characters.
This is one of the most common application layer attacks currently being used on the Internet. Despite the fact that it is relatively easy to protect against, there is a large number of web applications vulnerable.
This vulnerability affects /xxxx.php.