[ISN] Crypto weakness in smart LED lightbulbs exposes Wi-Fi passwords

http://arstechnica.com/security/2014/07/crypto-weakness-in-smart-led-lightbulbs-exposes-wi-fi-passwords/ By Dan Goodin Ars Technica July 7, 2014 In the latest cautionary tale involving the so-called Internet of things, white-hat hackers have devised an attack against network-connected lightbulbs that exposes Wi-Fi passwords to anyone in proximity to one of the LED devices. The attack works against LIFX smart lightbulbs, which can be turned on and off and adjusted using iOS- and Android-based devices. Ars Senior Reviews Editor Lee Hutchinson gave a good overview here of the Philips Hue lights, which are programmable, controllable LED-powered bulbs that compete with LIFX. The bulbs are part of a growing trend in which manufacturers add computing and networking capabilities to appliances so people can manipulate them remotely using smartphones, computers, and other network-connected devices. A 2012 Kickstarter campaign raised more than $1.3 million for LIFX, more than 13 times the original goal of $100,000. According to a blog post published over the weekend, LIFX has updated the firmware used to control the bulbs after researchers discovered a weakness that allowed hackers within about 30 meters to obtain the passwords used to secure the connected Wi-Fi network. The credentials are passed from one networked bulb to another over a mesh network powered by 6LoWPAN, a wireless specification built on top of the IEEE 802.15.4 standard. While the bulbs used the Advanced Encryption Standard (AES) to encrypt the passwords, the underlying pre-shared key never changed, making it easy for the attacker to decipher the payload. “Armed with knowledge of the encryption algorithm, key, initialization vector, and an understanding of the mesh network protocol we could then inject packets into the mesh network, capture the Wi-Fi details, and decrypt the credentials, all without any prior authentication or alerting of our presence,” researchers from security consultancy Context wrote. […]