Exzess: Hardware-Based RAM Encryption Against Physical Memory Disclosure
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The main memory of today’s computers contains lots of sensitive data, in particular from applications that have been used recently. As data within RAM is stored in cleartext, it is exposed to attackers with physical access to a system. In this paper we introduce Exzess, a hardware-based mitigation against physical memory disclosure attacks such as, for example, cold boot and DMA attacks. Our FPGA-based prototype with accompanying software components demonstrates the viability, security and performance of our novel approach for partial main memory encryption via memory proxies. The memory proxy approach will be compared to other existing mitigation techniques and possible further uses beyond encryption will be discussed, as well. Exzess effectively protects against physical attacks on main memory while being transparent to applications and the operating system after initialization.
KeywordsMemory encryption Memory disclosure Physical attacks
This work was partly supported by the German Research Foundation (DFG) as part of the Transregional Collaborative Research Centre “Invasive Computing” (SFB/TR 89).
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