What potential security risks are associated with allowing PHP scripts to access directories owned by different users?

Allowing PHP scripts to access directories owned by different users can pose a significant security risk as it can potentially lead to unauthorized access to sensitive files or data. To mitigate this risk, it is important to ensure that proper file permissions are set on directories and files, restricting access to only authorized users.

// Set proper file permissions on directories and files
// For example, to restrict access to only the owner:
chmod("/path/to/directory", 0700);
chmod("/path/to/file", 0600);