Break IC, Recover MCU, Microcontroller Reverse Engineering

Posts Tagged ‘extract fpga mcu firmware’

Security engineers are interested in the period of time for which an SRAM device will retain data once the power has been removed. The reason for this is as follows. Many products do cryptographic and other security-related computations using secret keys or other variables that the equipment’s operator must not be able to read out or alter. The usual solution is for the secret data to be kept in volatile memory inside a tamper-sensing enclosure. On detection of a tampering event, the volatile memory chips are powered down or even shorted to ground. If the data retention time exceeds the time required by an opponent to open the device and power up the memory, then the protection mechanisms can be defeated.

In the 1980s, it was realised that low temperatures can increase the data retention time of SRAM to many seconds or even minutes. With the devices available at that time, it was found that increased data retention started about −20°C and increased as temperature fell further. Some devices are therefore designed with temperature sensors; any drop below −20°C is treated as a tampering event and results in immediate memory zeroisation. We set out to repeat this work. Our goal was to find whether the memory devices available in the year 2000 exhibit the same behaviour.

Quoted from “Semi-invasive attacks – A new approach to hardware security analysis” writen by Sergei P. Skorobogatov.