Data transmission method of penetrating firewall

Usually, the firewall on the host will let us encounter some minor problems when we need to send the data to the back door for the target host. If you open a port (or even a new socket) for our own process, most firewalls will intercept it. Is there any way to "penetrate" these firewalls?

Let me introduce you to a way to "penetrate" the firewall to transfer important data on a small scale. However, you are not recommended to use this method in other situations.

In fact, my idea is very simple, since the firewall will intercept the unauthenticated process and release the data transfer of the validated process, then we will be other processes in the other process to allow data transfer socket handle to be used. The specific process is as follows:

1, identify the target process;

2, find the socket handle;

2, using DuplicateHandle () function to convert its socket to be able to use their own;

3, with the converted socket for data transmission.