php session handler can be overriden

php-session-handler.php

<?php
SessionHandler implements SessionHandlerInterface , SessionIdInterface {
/* Methods */
public close ( ) : bool
public create_sid ( ) : string
public destroy ( string $id ) : bool
public gc ( int $max_lifetime ) : int|bool
public open ( string $path , string $name ) : bool
public read ( string $id ) : string
public write ( string $id , string $data ) : bool
}