Undervolting allows attacks on Intel’s secure enclaves

Researchers at the University of Birmingham have identified a weakness in Intel's processors: by undervolting the CPU, Intel's secure enclave technology becomes vulnerable to attack. Modern processors are being pushed to perform faster than ever before - and with this comes increases in heat and power consumption. To manage this, many chip manufacturers allow frequency and voltage to be adjusted as and when needed - known as 'undervolting' or 'overvolting'. This is done through privileged software interfaces, such as a "model-specific register" in Intel Core processors. A team of researchers from the University of Birmingham's School of Computer Science along with researchers from imec-DistriNet (KU Leuven) and Graz University of Technology have been investigating how these interfaces can be exploited in Intel Core processors to undermine the system's security in a project called Plundervolt. New results, released today and accepted to IEEE Security & Privacy 2020 , show how the team was able to corrupt the integrity of Intel SGX on Intel Core processors by controlling the voltage when executing enclave computations - a method used to shield sensitive computations for example from malware. This means that even Intel SGX's memory encryption and authentication technology cannot protect against Plundervolt.