In our previous post, we looked at how smart meters were being introduced across multiple countries and regions, and why these devices pose security risks to their users. At their heart, a smart meter is simply... a computer. Let's look at our existing computers - whether they are PCs, smartphones, tablets, or embedded devices. Similarly, these smart meters are communicating via understood technologies: cellular connectivity, power-line networking, or the user's own Internet connection. With that in mind, we have to consider the possible threats - what could happen if a smart meter is compromised? Similarly, what are the problems that could result if the connectivity of a smart meter is disrupted? Let us see. Perhaps the most obvious risk is simple: meter tampering. If a smart meter can be hacked, inaccurate information can be sent back to the utility, allowing an attacker to adjust the reading and resulting in an inflated bill. Let's say, for example, that you have an argument with your neighbor. In revenge, if he can access your smart meter, you might see a rather large electric bill.
Figure 1. Hacking a neighbor's smart meter (A screenshot from our video highlighting attack scenarios)Of course, the bill can also change in the opposite direction. Let's say you're engaged in certain activities that require high levels of electricity... altcoin mining, for example. The biggest running cost for such an operation would be the electric bill. The smart meter could be hacked to have a lower reading - or, perhaps, in a location with time-varying electric rates, to make it look like the electricity was used at off-peak times? What are some other threats at the local, "retail" level when it comes to smart meters? Crime gangs (with smarts) may well find uses for smart meters too. Power savings are frequently promoted as a benefit of smart meter. However, power consumption is also a good way of checking if someone is in a home or not. Let's say that a vulnerability made it easy for somebody other than the homeowner or the utility to see what the power usage was. (It could be as easy as a poorly-designed API, mobile app, or website.) The smart meter would then essentially become a giant "please rob me" sign for properly equipped thieves. Alternately, if that smart meter can be controlled remotely, you now have an excellent way to carry out extortion. Such a nice house you have there, it'd be shame if anything bad happened to its power... The connectivity of the smart meters can also be a security risk. Some meters use the cellular network to provide the connection to the main servers of their utility. The utility would, of course, be paying for the bills of these meters. A truly determined person could abuse this "free" phone to make calls, send text messages, even connect to the Internet. Alternately, the smart meter may use the same Internet connection as the home. This represents a potential risk: if somebody was able to hack the smart meter from the outside, then that attacker would have access to the house's internal network. This would put your own internal network at risk of attack; it would be as dangerous as letting anyone connect to your home network. None of the above attacks are inevitable. You can build defenses against all of them. However, it is inevitable that somewhere, somehow, the defenses will fail. These attacks are possible, and we will have to figure out how to defend against them, especially once smart meters become more prevalent. All of the attacks I discussed above are essentially small-scale, however. What happens when you look at the security of not just individual meters, but the smart grid as a whole? That's what we will discuss in the third post in this three-part series on smart meters and smart grids. You can read parts 1 and 3 of this blog series here: Internet of Everything hub which contains our materials that discuss this emerging field.