Biblio

WhatsApp is one of the rare applications that has managed to become one of the most popular instant messaging applications all over the world. While inherently designed for simple and fast communication, privacy features such as end-to-end encryption have made confidential communication easy for criminals aiming to commit illegal acts. However, as it meets many daily communication and communication needs, it has a great potential to be digital evidence in interpersonal disputes. In this study, in parallel with the potential of WhatsApp application to contain digital evidence, the abuse of this situation and the manipulation method of multimedia files, which may cause wrong decisions by the judicial authorities, are discussed. The dangerous side of this method, which makes the analysis difficult, is that it can be applied by anyone without the need for high-level root authority or any other application on these devices. In addition, it is difficult to detect as no changes can be made in the database during the analysis phase. In this study, a controlled experimental environment was prepared on the example scenario, the manipulation was carried out and the prepared system analysis was included. The results obtained showed that the evidence at the forensic analysis stage is open to misinterpretation.

The IEEE Std. 1687 (IJTAG) was designed to provide on-chip access to the various embedded instruments (e.g. built-in self test, sensors, etc.) in complex system-on-chip designs. IJTAG facilitates access to on-chip instruments from third party intellectual property providers with hidden test-data registers. Although access to on-chip instruments provides valuable data specifically for debug and diagnosis, it can potentially expose the design to untrusted sources and instruments that can sniff and possibly manipulate the data that is being shifted through the IJTAG network. This paper provides a comprehensive protection scheme against data sniffing and data integrity attacks by selectively isolating the data flowing through the IJTAG network. The proposed scheme is modeled as a graph coloring problem to optimize the number of isolation signals required to protect the design. It is shown that combining the proposed approach with other existing schemes can also bolster the security against unauthorized user access as well. The proposed countermeasure is shown to add minimal overhead in terms of area and power consumption.