Analyzing the Vulnerabilities of External SDRAM on System-on-Chip Field Programmable Gate Array Devices

System-on-chip (SoC) field programmable gate array (FPGA) devices are becoming increasingly prominent in a vast range of applications. The fusion of the FPGA’s unmatched parallel computing capacity and flexibility with a full-bore processing system makes these devices extremely powerful. With recent technological progress, SoC FPGA devices are implemented in increasingly complex systems where security and safety are often issues of concern. To cater to these concerns, these devices are commonly fit with encryption and authentication capabilities to ensure the confidentiality and authenticity of externally stored bitstreams, firmware, and bootloaders. However, while much effort is placed into securing these partitions when stored in external memory, little attention seems to be paid to the security of this data once it is decrypted for execution. This article investigates how vulnerable systems are to attacks that target decrypted data during execution. We demonstrate that data stored in external synchronous dynamic random access memory (SDRAM) can provide access to trusted and secured interfaces of SoC FPGA devices even with diligently applied security features.