What are the potential issues with using $HTTP_POST_VARS instead of $_POST in PHP scripts?

Using $HTTP_POST_VARS instead of $_POST in PHP scripts can lead to security vulnerabilities as $HTTP_POST_VARS is a deprecated feature and is not recommended for use. To fix this issue, it is recommended to use the $_POST superglobal array instead for handling form data securely.

// Using $_POST instead of $HTTP_POST_VARS
if ($_SERVER["REQUEST_METHOD"] == "POST") {
    $username = $_POST["username"];
    $password = $_POST["password"];
    
    // Rest of the code
}