Extracting Keys from SoC Zigbee Chips

by Travis Goodspeed <travis at radiantmachines.com>

Last week, at Black Hat Briefings, I presented a short paper entitled Extracting Keys from Second Generation Zigbee Chips. Though brief, the paper is vitally important reading for anyone shipping a product with chips from Chipcon and Ember. The paper includes a method by which keys may be extracted from these chips, as well as a software method for defending Chipcon devices against the attack. All EM2xx chips are vulnerable, as are all of the 8051-based Chipcon radios, such as the CC2530. This is not the same as my attack against first generation, discrete radios.

Black Hat '09, Defcon 17

Howdy y'all,

I'll be taking a trip to Vegas this summer for Black Hat and Defcon. Abstracts below are as submitted to the conferences, and there will be a tool released, of the extra-neighborly sort, at Black Hat. I also expect to do some hands-on stuff at Defcon's hardware hacking village.

For Defcon,
Locally Exploiting Wireless Sensors
Wireless sensors are often built with a microcontroller and a radio chip, connected only by a SPI bus. The radio, not the MCU, is responsible for symmetrical cryptography of each packet. When the key is loaded, it is sent as cleartext over the SPI bus, and an attacker with local access can steal the key using a few syringe probes and readily available hardware. This attack and other local attacks against wireless sensor networks will be presented in detail, including a live demo of an AES128 key being extracted from an operational network. Following the conclusion of the lecture, audience members will be brought onstage to perform the attack themselves on various pieces of example hardware.

For Black Hat,
A 16 bit Rootkit and Second Generation Zigbee Chips
This lecture in two parts presents first a self-replicating rootkit for wireless sensors, then continues with recent research into the security of second generation Zigbee radio chips such as the CC2430/2431 and the EM250.

--Travis Goodspeed
<travis at radiantmachines.com>