Brute Force IC Break Example
Brute Force IC Break is a process through which the inner circuitry pattern of MCU will be changed include decapsulation, focus ion beam and laser cut ways;
Brute force IC break’s one good example could be the password protection scheme used in microcontrollers, such as the Texas Instruments MSP430 family. The password itself is 32 bytes (256 bits) long which is more than enough to withstand direct brute force MCU breaking methods.
But the password is allocated at the same memory addresses as the CPU interrupt vectors. That, firstly, reduces the area of search as the vectors always point to even addresses within memory. Secondly, when the software gets updated, only a small part of the password is changed because most of the interrupt subroutines pointed to by the vectors are very likely to stay at the same addresses.
As a result, if the IC code extractor knows one of the previous passwords he could easily do a systematic search and find the correct password in a reasonable time.