It is possible to monitor and control float trucks, public bus or delivery vans from the internet , obtaining their speed, position, and a lot other parameters. You can even control some parameters of the vehicle or hack into the canbus of the vehicle remotely.
Those vehicles have a Telematics Gateway Unit (TGU) device and a 3g/4g/gprs/lte/edge/HDSPA modem to connect to the internet, with a public I.P. address.
There are thousands of TGU connected to the internet, with no authentication at all and with administrative interfaces through a web panel or a telnet session.