What potential issues can arise when using PHP session variables in a script?

One potential issue when using PHP session variables is that they can be vulnerable to session hijacking or fixation if not properly secured. To mitigate this risk, it's important to use session_regenerate_id() to generate a new session ID and prevent attackers from accessing the session data.

session_start();

// Regenerate session ID to prevent session fixation/hijacking
session_regenerate_id();