25C3 -

25th Chaos Communication Congress
Nothing to hide

Travis Goodspeed
Day Day 1 (2008-12-27)
Room Saal 3
Start time 20:30
Duration 01:00
ID 2839
Event type lecture
Track Hacking
Language used for presentation en

Cracking the MSP430 BSL

Part Two

The Texas Instruments MSP430 low-power microcontroller is used in many medical, industrial, and consumer devices. When its JTAG fuse is blown, the device's firmware is kept private only a serial bootstrap loader (BSL), certain revisions of which are vulnerable to a side-channel timing analysis attack. This talk continues that from Black Hat USA by describing the speaker's adventures in creating a hardware device for exploiting this vulnerability.

While the previous part focused on the discovery of the timing vulnerability and its origin, this lecture will focus on the exploitation. Topics include a brief review of the vulnerability itself, PCB design and fabrication, the malicious stretching of timing in a bit-banged serial port, observation of timing differences on the order of a microsecond, and the hell of debugging such a device.