Pre-requisites Here are some pre-requisite knowledge, that might help you in understanding the blog even more: Little knowledge about C# Little knowledge about sysinternals Some knowledge about process injection techniques Knowledge about P/Invoke Introduction This blog is about, how I was able to recreate the EarlyBird UserAPC process injection technique with DInvoke. There is also a POC version of this technique on my repository : EarlyBird It is a very simple code execution technique.