Visible to the public Biblio

Filters: Author is Obermaier, Johannes  [Clear All Filters]
2022-10-16
Hauschild, Florian, Garb, Kathrin, Auer, Lukas, Selmke, Bodo, Obermaier, Johannes.  2021.  ARCHIE: A QEMU-Based Framework for Architecture-Independent Evaluation of Faults. 2021 Workshop on Fault Detection and Tolerance in Cryptography (FDTC). :20–30.
Fault injection is a major threat to embedded system security since it can lead to modified control flows and leakage of critical security parameters, such as secret keys. However, injecting physical faults into devices is cumbersome and difficult since it requires a lot of preparation and manual inspection of the assembly instructions. Furthermore, a single fault injection method cannot cover all possible fault types. Simulating fault injection in comparison, is, in general, less costly, more time-efficient, and can cover a large amount of possible fault combinations. Hence, many different fault injection tools have been developed for this purpose. However, previous tools have several drawbacks since they target only individual architectures or cover merely a limited amount of the possible fault types for only specific memory types. In this paper, we present ARCHIE, a QEMU-based architecture-independent fault evaluation tool, that is able to simulate transient and permanent instruction and data faults in RAM, flash, and processor registers. ARCHIE supports dynamic code analysis and parallelized execution. It makes use of the Tiny Code Generator (TCG) plugin, which we extended with our fault plugin to enable read and write operations from and to guest memory. We demonstrate ARCHIE’s capabilities through automatic binary analysis of two exemplary applications, TinyAES and a secure bootloader, and validate our tool’s results in a laser fault injection experiment. We show that ARCHIE can be run both on a server with extensive resources and on a common laptop. ARCHIE can be applied to a wide range of use cases for analyzing and enhancing open source and proprietary firmware in white, grey, or black box tests.
2017-06-27
Obermaier, Johannes, Hutle, Martin.  2016.  Analyzing the Security and Privacy of Cloud-based Video Surveillance Systems. Proceedings of the 2Nd ACM International Workshop on IoT Privacy, Trust, and Security. :22–28.

In the area of the Internet of Things, cloud-based camera surveillance systems are ubiquitously available for industrial and private environments. However, the sensitive nature of the surveillance use case imposes high requirements on privacy/confidentiality, authenticity, and availability of such systems. In this work, we investigate how currently available mass-market camera systems comply with these requirements. Considering two attacker models, we test the cameras for weaknesses and analyze for their implications. We reverse-engineered the security implementation and discovered several vulnerabilities in every tested system. These weaknesses impair the users' privacy and, as a consequence, may also damage the camera system manufacturer's reputation. We demonstrate how an attacker can exploit these vulnerabilities to blackmail users and companies by denial-of-service attacks, injecting forged video streams, and by eavesdropping private video data - even without physical access to the device. Our analysis shows that current systems lack in practice the necessary care when implementing security for IoT devices.