Securing LED Networks in the Age of the Internet of Things

Recently, in Nuevo Arenal, a little sleepy village in the Guanacaste region of Costa Rica, a dozen criminals cut the lights to the town’s main street during the quiet 3 a.m. hour, and then injured a gas station attendant, a hardware store security guard and a security guard hired by the town. Once the lights were cut, carrying on with their crime spree was pretty easy. As evidenced by this example, gaining control of lighting systems enables hacking, and many smart lighting systems lack an adequate security presence. As LED networks connect to the Internet of Things (IoT), the vulnerabilities are becoming more obvious — but the solutions to this problem may be closer than expected.

Benefits to LED use

LED use is certainly compelling based on the technology’s ability to cut general lighting energy use by a huge percentage, generating big savings in the forms of both money and reduction in carbon footprint. LEDs have many additional benefits including:

• Form factor
• Minimal maintenance
• Solid performance over a wide temperature range
• Color control
• Long life
• Dimming
• Appropriate for a wide range of applications
• Light goes where intended rather than spread evenly (as light does from fluorescents and incandescent bulbs)

Unlike the alternatives, LEDs can be connected to an IoT network. And, within that network, Gartner estimates 26.5 billion objects will be embedded by 2020. A high percentage of these devices are fairly recent designs, and in their race to get to market quickly, are often devoid of long-standing security protection. Therein lies the problem. These newer devices are meeting an older network and security methods, and the environment is replete with vulnerable services, authentication bypass schemes and default passwords. What exists is a junction of very smart LEDs and not-so-smart networks — and the weaknesses are becoming increasingly evident.

Vulnerabilities come to “light”

Two of the most notable cases of LED hacking are (thankfully) the work of researchers. It must be stressed that this is a rapidly moving marketplace and design environment. As problems surface, fixes need to be developed and deployed rapidly.

The Philips Hue LED was hailed as a significant advance in lighting, but missed the security mark faced by all devices connected to the IoT. Because of its open APIs and the trust of local devices, the Hue was both easy to program and use. As a result, Nitesh Dhanjani, a security researcher, was able to hack into the Hue’s closed system, and caused a blackout using malware. As long as the bridge (router) was installed, the lights remained off. Dhanjani published a paper that outlines the Hue’s vulnerabilities including IFTTT recipes, Facebook and such protocols as ZigBee Light Link. Placing the malware on a PC is the method Dhanjani used, which means that the network was actually hacked rather than the LED itself. It was a trusted device that issued the command to turn the lights off. In this case, the fix is improved security at the PC level.

More recently, a researcher successfully hacked into a LIFX Wi-Fi LED network that was integrated with the Nest home platform from Google. Researchers identified specific packets where Wi-Fi network credentials were shared and requested Wi-Fi details, all without ever alerting the application. Once in the Wi-Fi network, the hackers switched out some firmware for their software/hardware and they were able to take flash memory from each chip, reverse engineering the firmware. While it wasn’t a simple hack, it’s a critical one.

In this case, the architecture was based on the 802.15.4 6LoWPAN wireless mesh network. In this system, although all bulbs are receiving commands over the mesh network, they do so through the master bulb, which is connected to Wi-Fi. A research group from Context Information Security, an IT security firm, was able to access packets that shared the encrypted network configuration.

For this hack, six researchers broke open the bulb to identify the processors that resided on the PCB. Since the bulb used AES data encryption, the researchers found that the encrypting and decrypting parties had access to the same pre-shared key; each device had a constant global key. Once the key is accessed in one device, the same key can be used to decrypt messages from all devices or any LIFX bulb. Fortunately, to accomplish this breach, hackers had to be within approximately 100 feet of the wireless range to access the network, meaning that large corporate campuses are most likely immune. Once this vulnerability came to light, LIFX rapidly updated its firmware and added encryption to its network, thereby fixing the problem.

Given that LEDs are being widely used in cities, especially for street lighting, sports facilities, and corporate facilities, a primary design consideration should be the security of the systems used. And, realization of the dangers is finally at hand.

Solutions to date

While an understanding of LED-based security threats is growing, most companies are still in the dark. One solution, given the sheer number of devices in use as well as the need for greater security, is to segment the network. However, with this option, wireless access points and separate cables can be costly.

A new platform, called the Light Sensory Network (LSN) is another option. This digital sensor network uses cloud services for sensor and network-enabled lighting so that LED luminaires are sensor-equipped, solid-state and smart devices that capture and transmit data. Placed 20 feet or more in the air, the LSN senses information surrounding distributed-light fixtures, such as real-time parking or the movement of goods and objects. The LSN gathers data such as parking availability and provides the data to smart- parking application developers through an open API. Engineers can expect to see more of these types of solutions offering ever greater cost-effective alternatives.

The future

Whether on campus or in the home, wireless radio signal technology has further opened the door to hacking vulnerabilities. At each juncture, wireless communications networks will face security risks. For devices, including those produced by LED manufacturers, it is important to note that the device itself is only part of the issue; the network must also be considered. For that reason, having a thorough understanding of wireless networks and the security possibilities is critical. Periodic security testing of the network is necessary, as are the application of security enhancements and patches. Also, the monitoring of standards and new products is imperative, as is involvement in the standards groups that apply when possible. In this day and age, there will always be potential for new hacking opportunities, at least until the market matures.

As new applications abound, open source security will also come to the forefront. The combination of hardware/software security protection versus software only will make hacking more difficult. While strides have been made to invent solutions to ensure security that is both low cost and reliable, it will take a few years before these solutions can really make an impact. There is no doubt that leading LED manufacturers, such as Avago, Bridgelux, Omron, OSRAM and others will be actively involved in the development and delivery of solutions to make the industry more secure.

As with any rapidly evolving industry, considering all of the potential pitfalls does not typically occur in early designs. As evolution takes place, so does the implementation of features and benefits that earlier iterations lack, especially when those iterations involve apparent flaws. As the design of LED lights continues to improve, and platforms like the LSN grow in popularity, each luminaire will use a broader set of sensors, cloud applications and secure networking. These systems will enable the collection, analysis and monitoring of data and the ability to act on it in real time, with an eye toward improved safety and security.