chameleon solution BsidesSF 2020

Introduction BsidesSF had really really good reverse engineering challenges, but I loved two challenges. One windows reverse challenge called chameleon and another esp32 firmware reverse challenge called smart-locky which I didn’t manage to solve in time. The challenge Problem statment We are given two files chameleon.exe and flag.png.enc, this looks trivial enough we need to reverse the encryption algorithm to give us the original flag.png. The problem statment also says that file was encrypted in the last months.