What are the potential issues with using session variables in PHP forms?

One potential issue with using session variables in PHP forms is that they can be vulnerable to session hijacking or fixation attacks if not properly secured. To mitigate this risk, it is recommended to regenerate the session ID after a user logs in or performs a sensitive action. This helps prevent unauthorized access to the session data.

// Regenerate session ID after login or sensitive action
session_regenerate_id(true);