In this blog post, I will explain how I reverse engineered a Cobalt Strike dropper and obtained its payload. The payload is a custom executable file format based on DLL. The dropper decrypts, loads, and executes the payload. Initially, I thought this must not be a PE executable at all, but I gradually realized it was. Much of the effort was spent on fixing the file so it could be loaded by Binary Ninja for further analysis.
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