How can PHP developers prevent data leakage between user sessions?

PHP developers can prevent data leakage between user sessions by ensuring that session data is properly sanitized and validated before being stored or accessed. They can also implement secure session handling techniques such as using HTTPS, setting session cookie parameters securely, and regularly rotating session IDs. Additionally, developers should avoid storing sensitive information in session variables and should always encrypt any sensitive data before storing it in the session.

// Prevent data leakage between user sessions
session_start();

// Set session cookie parameters securely
session_set_cookie_params([
    'httponly' => true,
    'samesite' => 'Strict'
]);

// Regularly rotate session IDs
session_regenerate_id(true);

// Encrypt sensitive data before storing it in the session
$_SESSION['user_id'] = encryptData($user_id);

// Sanitize and validate session data before accessing it
$user_id = decryptData($_SESSION['user_id']);