Hardware prefetchers are an optimization in modern CPUs that predict memory accesses and preemptively load the corresponding value into the cache. Previous work showed that the internal state of hardware prefetchers can act as a side channel, leaking information across security boundaries such as processes, user and kernel space, and even trusted execution environments.

Large botnets like Mirai, with 600,000 infected devices, prove that cyber criminals have recognized the potential of attacks against the fast-growing Internet of Things. Moreover, recent critical vulnerabilities like Ripple20 and Amnesia:33 show that taking over a remote system via the network is a real threat. Alarmingly, modern strains of malware rely on exploiting such vulnerabilities to spread, with an increasing tendency. Hence, effective techniques to mitigate the consequences of modern IoT malware are necessary.