A Cautionary Note on Building Multi-tenant Cloud-FPGA as a Secure Infrastructure

Security concerns have been raised for multi-tenant cloud-FPGA in many recent works. While these existing works focused on studying the security of diverse cloud-FPGA applications, such as Advanced Encryption Standard (AES), the vulnerabilities associated with the inherent FPGA components are so far under-explored. For the first time, we investigate the robustness of a commonly used communication protocol for data exchange, Advanced eXtensible Interface (AXI), against fault injection attacks in a multi-tenant cloud-FPGA environment. We build an experimental setup with a commodity FPGA development kit and launch fault injection attacks on the shared power distribution network (PDN). To study the in-depth effects of such attacks, we characterize the voltage glitches of different attack patterns in a non-invasive manner, i.e., using electron magnetic measurement. We also mimic the real-world data transmissions using two crafted datasets with different statistical characteristics. The experimental results demonstrate the unique security vulnerabilities of the current AXI protocol in the context of a multi-tenant cloud-FPGA. Last, we discuss potential defense strategies against these vulnerabilities.