I'm using a Hotspot provided by Cisco in a library and when first connecting to the Wireless network, Firefox prompts me to login to network in order to have Internet access (expected and works fine). However, once the time session expires Firefox will sometimes prompt again to login. When this fails and internet access is abruptly ended, I've to reconnect to the Wireless network and have Firefox prompt to login.

This is a security vulnerability as someone could advertise the BSSID of the router and have victims connect to their Hotspot instead of the true one.