@ro0t I traced your obsfuscations, IAT, and sections, no brute force. I found static strings such as Nickname, serial key, etc., in the rdata section. The main function was to set up the stack frame and then jump to the .ll section with MBA chains. I spent a while trying to make sense of it, but got nowhere with it. So, I wrote a small emulator to fake out the Windows structure (honestly, I am not on Windows these days), .a2l runtime needs (TED/PEB/LDR it walks to resolve the VirtualAlloc, which is kind of neat) and hooked IAT functions. Figured out the program does malloc for parsing the input serial bytes, then malloc for a 16-byte buffer where it stores the result of some custom 128-bit hash over the nickname, and the comparison between the two is done inline, so you can't just set a breakpoint to check. And then I read the computed hash from the heap, and that's your serial. I think it's really solid work. The MBA transforms did their job; I genuinely could not recover the logic. The .a2l runtime with its own stack and PEB walking dispatcher is a nice touch too. The thing that let me bypass all of it was that the I/O boundary is still clean and IAT calls to printf, fgets, and malloc are right there unprotected, so hooking them gives you the inputs and outputs without having to understand anything in between.