What are the potential security risks of automatically inserting data from the Windows clipboard into a form using PHP?

Automatically inserting data from the Windows clipboard into a form using PHP can pose a security risk known as cross-site scripting (XSS). This is because the data from the clipboard may contain malicious scripts that could be executed on the website. To mitigate this risk, it is important to sanitize the data before inserting it into the form to prevent any malicious code from being executed.

// Sanitize data from clipboard before inserting into form
$clipboard_data = $_POST['clipboard_data']; // Assuming the clipboard data is sent via POST

// Sanitize the data using htmlentities function
$sanitized_data = htmlentities($clipboard_data);

// Insert the sanitized data into the form
echo '<input type="text" name="data" value="' . $sanitized_data . '">';