@dalias @tinker It's not HTTPS that I'm worried about. I may have mentioned the wrong type of attack.
One example of a vulnerability I found was on the WiFi in my old student halls. The entire site was on one subnet, seemingly with no separation. I could ping PlayStations on the other side of the building and turn people's speakers on at 3AM, all from the comfort of my own room using nothing more than an Android tablet. This didn't fill me with confidence about other aspects of the network.