Is it possible to find the modifications between a original DLL file and a modified one using x64dbg?
And, if I can't do it with x64dbg, what tool would be better than a debugger to find the modifications done on assembly code between the two files?
Is it possible to find the modifications between a original DLL file and a modified one using x64dbg?
And, if I can't do it with x64dbg, what tool would be better than a debugger to find the modifications done on assembly code between the two files?
You shouldn't use a debugger to search for differences. You should use a diff tool. Of course, most diff tools work on ASCII text, but there are some that deal with binary files.
Some examples:
There are more and you probably will find one that matches exactly your need. If you would like to see your modifications in a nice visual manner with already bytes being presented as opcodes there are some options too. I haven't used them (so can't give you my recommendations) but there are at least two that I know of:
In Windows, perhaps the simplest possibility is the built-in File Compare command with its /B (binary) switch, to be used from the command-line. It lists all different bytes together with their file offset.
Usage:
fc /B filepath1 filepath2