Microsoft & quot; backdoor & quot; ntsd discovery and Removal

The so-called "Microsoft's" backdoor "is the remote debugging function of ntsd.
What is ntsd first: "ntsd is a built-in process debugging tool. NTSD is powerful and complex ."
 
 





 
This legendary Microsoft "backdoor" is also an external chain Backdoor
 
You also need to open the port. If you use netstat-an to view the port, an abnormal connection will also occur.
 
 



However, this "backdoor" is a natural anti-virus solution.
Why? This is because it is a system file! Anti-virus software cannot be killed.
 
 
 
If the "backdoor" is started in service mode, the permission is higher.
 
However, if he is set to prohibit permissions, it may be difficult to use them in the future.
 
This requires a very powerful firewall provided by Windows to filter such ports.
 
Control Panel-Windows Firewall
 
 

 
 
Select enable and allow exceptions
 
 

 
 
 
Add port, 80, 21, and terminal port
 

 
 
If the Pasv mode is used for FTP, use the Add allowed program.
 
 
 
 
In this way, all external chain backdoors cannot be connected because the ports are blocked outside the firewall.