Note to people outside of the US who are worried about this:
The rest of the world uses 3G/4G modems in their smart meters, they are usually also connected to a different APN than generic mobile data. Sometimes multiple meters are connected to a central hub with a physical wire (in apartment buildings for example). The hub is then the only gateway to the internet.
The hack in question is only viable because of the weird way US smart meter collection is done.
US Smart Meters use RF to shout out their values everywhere like an RF beacon. A power company vehicle drives around the neighbourhood, collecting the values, storing them and moves on.
The rest of the world uses 3G/4G modems in their smart meters, they are usually also connected to a different APN than generic mobile data. Sometimes multiple meters are connected to a central hub with a physical wire (in apartment buildings for example). The hub is then the only gateway to the internet.
The hack in question is only viable because of the weird way US smart meter collection is done.
US Smart Meters use RF to shout out their values everywhere like an RF beacon. A power company vehicle drives around the neighbourhood, collecting the values, storing them and moves on.
Source: I did smart metering software for L+G.