What are the potential security risks of displaying message boxes directly in the URL for users to access in PHP?

Displaying message boxes directly in the URL can expose sensitive information to potential attackers, such as error messages, debug information, or internal system details. This can lead to security risks like information disclosure, cross-site scripting (XSS) attacks, and unauthorized access to system data. To mitigate these risks, it is recommended to store sensitive messages in session variables or display them in a secure manner without exposing them directly in the URL.

// Store message in session variable
session_start();
$_SESSION['message'] = "This is a secure message.";

// Redirect to a secure page to display the message
header("Location: secure_page.php");
exit;