Thursday, April 9, 2009

Hacking the BIOS of Fujitsu Siemens Laptops for Fun and Profit, Part Deux

Apparently, FSI hasn't done a much better job for the Amilo Pro series: this time, they've used the table of the CCIT-CRC16 algorithm (!) for a rather simplistic hashing algorithm. Lesson learned: never trust your data with security schemes which rely purely on obfuscation.
I have released the script and binaries for Windows under the GPL.

I want to thank blAck for providing me with some memory dumps which have made the reverse engineering considerably easier.

Update: I've made slight adaptions to the script so it should also work for 5x4 hexadecimal codes.

Edit: A more thorough explanation is here.