Discovered by Check Point Research and demonstrated in a video, the flaw relates to the Zigbee communication protocol used by Philips Hue bulbs and a number of other smart home devices, including Amazon's Ring, Samsung SmartThings, Ikea Tradfri, and Belkin's WeMo.
According to the security researchers, the vulnerability could allow a local attacker to take control of Hue light bulbs using a malicious over-the-air update and cause the bulbs to exhibit random behavior and become uncontrollable. If the user then deletes the bulb and re-adds it in the Hue app, the attacker is able to gain access to the Hue bridge.
The hacker-controlled bulb with updated firmware then uses the ZigBee protocol vulnerabilities to trigger a heap-based buffer overflow on the control bridge, by sending a large amount of data to it. This data also enables the hacker to install malware on the bridge – which is in turn connected to the target business or home network.Every Philips Hue Hub connected to the internet should have automatically updated itself to version 1935144040, which patches this specific vulnerability. Users can check themselves by looking to see if any updates are available for the Hue app.
The flaw actually relies on a vulnerability that was originally discovered in 2016 and which can't be patched, as it would require a hardware update to the smart bulbs.
"Many of us are aware that IoT devices can pose a security risk," said Yaniv Balmas, Head of Cyber Research at Check Point Research. "But this research shows how even the most mundane, seemingly 'dumb' devices such as lightbulbs can be exploited by hackers and used to take over networks, or plant malware."