Hello, Vekia
No, i do not use such a module. at first i was thinking that i was going to get a message saying you are not logged in, as fast i tryd to navigate around. but i was able to go access everything inside this customers account, like order history etc, and that made be surprised and worried. but since you are saying its quite impossiible then i dont know, i only know what happened to me. so unless it have or will happen to anyone else i guess it will just be a mystery for me.
greetings
Marius Christiansen