CarPlay sharing location with passenger’s iPhone

A passenger plugged their iPhone into my car to navigate somewhere, but didn’t have CarPlay enabled so my car displayed an “unable to connect” message and we just unplugged the phone. When we parked, though, the passenger got a Parked Car alert to their iPhone...! I’ve had other friends plug into CarPlay in the past, and now I’m nervous that they can see my car’s location whenever they want. How do I disable that now and prevent it in the future?