eFuzz: A Fuzzer for DLMS/COSEM Electricity Meters

Abstract

Smart grids enable new functionalities like remote and micro management and consequently, provide increased efficiency, easy management and effectiveness of the entire power grid infrastructure. In order to achieve this, smart meters are attached to the communication network, collecting fine granular data. Unfortunately, as the smart meters are limited devices connected to the network and running software, they also make the whole smart grid more vulnerable than the traditional grids in term of software problems and even possible cyber attacks. In this paper, we work towards an increased software security of smart metering devices and propose a fuzzing framework, eFuzz, built on the generic fuzzing framework Peach to detect software problems. eFuzz tests smart metering devices based on the communication protocol DLMS/COSEM, the standard protocol used in Europe, for possible faults. Our experiments prove the effectiveness of using an automated fuzzing framework compared to resource demanding, human made software protocol inspections. As an example, eFuzz detected between 10 and 40 bugs in different configurations in less than 3 hours while a manual inspection takes weeks. We also investigate the quality of the eFuzz results by comparing with the traditional non-automated evaluation of the same device with respect to scope and efficiency. Our analysis shows that eFuzz is a powerful tool for security inspections for smart meters, and embedded systems in general.