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An Open JTAG Debugger

Travis Goodspeed

Travis Goodspeed explores an open jtag debugger at DEF CON 17, examining jtag and practical defenses.

Summary

Architecture and Background

An Open JTAG Debugger Travis Goodspeed Engineer of Superior Buckles, Goodspeed & Gourneau While it's simple enough to build a "Wiggler" JTAG adapter for the PC parallel port, there is very little open hardware for performing high-speed programming of JTAG devices by USB. This lecture introduces the GoodFET, an open source USB JTAG adapter which can be reflashed to support the programming and debugging of any number of chips.

Vulnerability Analysis

Both hardware and firmware are compared to that of a similar, commercial design. This lecture will also cover the details of the JTAG standard and a few of its competitors, as well as the possibility of attacking these debugging modes when access has been denied or restricted.

Exploitation and Demonstrations

Travis Goodspeed is a neighborly reverse engineer from Southern Appalachia. He has been exploiting and reverse engineering wireless sensors since writing the first stack overflow exploit for them in 2007.

Remediation and Defensive Strategies

His recent projects have included a timing attack on the MSP430 bootstrap loader and an extra-neighborly party-mode belt buckle in the shape of Tennessee. For copies of the slides and additional materials please see the DEF CON 17 Archive here:

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