DLL Hijacking

Hey, Our penetration testers noticed that some DLLs that are used by the app/game are not found when the app/game starts.
Process Monitor:

They were able to replace it with a "malicious" tdh.dll (which normally is found in C\Windows\System32) and execute some code.

Is that dll used by the Unity Engine? What would be solution in this case? (Code signing, forcing Unity Engine to load only signed libraries, etc.)

 

Found an older post but still not answers the question: Prevent Dll hijacking - Unity Forum
will move to Unity support.