How can JavaScript scripts potentially affect PHP sessions, and what precautions should be taken to prevent session-related issues?

JavaScript scripts can potentially affect PHP sessions by making unauthorized changes to session variables or destroying the session altogether. To prevent session-related issues, it is important to validate and sanitize all user input, avoid storing sensitive data in client-side cookies, and implement proper session management techniques such as using session_regenerate_id() to prevent session fixation attacks.

// Start a secure session
session_start();

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