Secure Smart Homes Need Control on Site, not in the Cloud
By Simon Hunt, CTO - Home Gateway Security, Intel Security
Simon Hunt, CTO - Home Gateway Security, Intel Security
The smart home and the Internet of Things in the home are increasingly newsworthy lately, and for good reason. Who can deny the attractiveness of the “digital butler” experience—as your smart home saves energy and makes life more convenient? Automated lighting, learning thermostats, Wi-Fi enabled door bells with cameras, and smartphone notification that you left the garage door open: Most of us would find these features valuable.
With this convenience, though, come additional risks, such as the handy two-way Wi-Fi enabled baby monitor that was hacked to allow an individual to shout profanity at the sleeping child, and the reported attacks against home routers to modify DNS settings and steal personal information. We also eagerly await the discoveries from DEFCON 2015’s IOT Hacking Village, a competition designed specifically to find vulnerabilities in popular home IOT devices.
One partial advantage for homeowners is that the current focus of attack is on Internet-connected home IOT devices. There’s no way a remote hacker can gain access to your X10 or Insteon lights if you don’t have an X10-to-Internet gateway, and there’s no way to access your Zigbee door locks unless you connect them to the Internet, or the hacker is standing a few feet from your door.
Although Internet-connected home IOT devices are obviously valuable, they are not the sum total of the home IOT market.
Manufacturers are, of course, eagerly pursuing the home IOT market with Internet-connected devices. The idea of remotely controlling and interacting with our homes while we’re away is extremely compelling. Knowing the garage door is open when you’re at work is far more useful than knowing it’s open when you’re in the home, and changing your home heating settings when you know you’re going to delayed (or early), equally so.
Other advantages to an Internet connection include having weeks of security camera footage stored in the cloud, saving us from having to store the video at home, and the cost savings of moving the intelligence from the individual devices into cloud-based services.
Cloud connectivity, using someone else’s computer to offload processing, is currently a band-aid to reduce a product’s time to market and decrease the per-device cost. As an example, one of the most popular consumer IOT ecosystems requires broadband connectivity to turn a light on and off, or to open a door, even if you’re physically at home. Yet there’s no technical reason why an Internet service is required to broker a conversation between two devices on the same Wi-Fi network.
Given that home IOT can be interconnected to various degrees, we should consider the overall risk of the implemented ecosystem, not just the individual devices we install. This risk changes depending on the sophistication of the home in question.
The disconnected smart home
If the home has no Internet connection (or there is no bridge between the home IOT devices and the home Wi-Fi/Internet connection), there is minimal risk. Connection schemes such as X10, Zigbee, and Z-Wave are “localized”; a physical presence within their reception range is required. Many automation systems, such as Lutron and Insteon, donot require any Wi-Fi or Internet connection.
To be hacked, someone has to physically come to your home, a step the smart home security system is designed to mitigate.
"We also eagerly await the discoveries from DEFCON 2015’s IOT Hacking Village, a competition designed specifically to find vulnerabilities in popular home IOT devices"
Disconnected devices communicating with a home-only connected hub
The second case involves home IOT devices that connect to a Wi-Fi hub to allow them to be controlled via PCs, smartphones, etc. One example is Phillips Hue: the individual light bulbs talk via Zigbee to a hub, which connects to Wi-Fi to allow control through smartphones and tablets.An Internet connection is not required to control the system.
For hackers to compromise this architecture, they need a footprint within the home network.This could be a compromised PC or home router, but they can’t simply come from the Internet and directly attack the home hub.
Appropriate endpoint anti-malware products assist greatly in mitigating the risk, as does using WPA2 or better Wi-Fi encryption to prevent intruders from gaining access to your home network.
Internet-connected devices and devices with Internet-connected hubs
The most risky situation, and the one currently most under attack, allows devices (or their hub) to talk directly to the Internet. The infamous example of the compromised baby camera was simply an Internet-accessible device using default passwords.
Hacking websites trawl the Internet looking for connected security cameras using weak or default credentials. Any device directly accessible from the Internet needs the highest level of designed-in security and attention, because they are the most accessible and easiest to probe for weaknesses.
Unfortunately the trend in home IOT is to offer Internet-connected devices. Given the rapid evolution of this market and number of companies competing for a share, information security often becomes an afterthought.
At the moment, there are few ways to protect such an environment, other than to trust that the device and hub manufacturers have implemented robust security, and that any vulnerability will be quickly patched. However, it may be the homeowner’s responsibility to apply such patches—making it vital that you understand what devices you have, how they obtain updates, and any known vulnerabilities.
The Future
The security industry predicts significant changes in the home IOT space during the next decade. Smarthomes are moving from cool to useful, but an Internet outage that knocks out the lights is something the average homeowner won’t tolerate. Processing and intelligence need to move back into the home, under the homeowner’s control, especially for automation and security features.
Having the intelligence of your home IOT depend on cloud processing will naturally be replaced with a smart “black box” in a closet, perhaps merged with media storage and entertainment features.
The “smart home” of today is really a dumb home connected to a smart cloud. That must change, as we empower the next generation of homes to be smart in their own right.
