Are there any potential security risks associated with storing user IDs in sessions in PHP?

Storing user IDs in sessions in PHP can pose a security risk if the session data is not properly secured. An attacker could potentially hijack a user's session and impersonate them by stealing their session ID. To mitigate this risk, it is recommended to regenerate the session ID whenever a user logs in or changes privilege levels.

// Regenerate session ID to prevent session fixation attacks
session_regenerate_id(true);