Mostly they try to blow you up as soon as the scan detects the passenger.
If your ship is fast enough you can boost out of range before the scan completes then try and sneak in using stealth techniques or set up so you can get through the mail slot at around 300 plus so they don’t get time to complete the scan.
So essentially it is a smuggling job and as long as your ship is very fast with lots of boost and can run extremely cold you will be fine.
If your ship is slow with limited boost capacity and can’t enter a station while silent running then illegal passengers will be even more trouble than normal ones.