Case study – reverse engineering during malware analysis

Another field of work that requires more advanced reverse engineering skills is malware analysis. Malware researchers spend days and weeks looking at disassembled and decompiled binaries to deduce the application flow. Let's take another case study.

During the analysis of a malware mobile app, it was noticed that the application somehow modifies its behavior depending on factors such as country, language, and applications installed. For a device in the United States, with the English language, and that had financial/banking apps, the application would try to read messages and the transaction history. However, on a different device in a different country, and with dating apps installed, it would try to inject ads in the traffic of other apps. Such a change in behavior cannot be noticed if the application is only used on one device.

However, a good analysis of the disassembled application binary and its associated...