Let's look at port 445 first:
Port 445 is a net file system (CIFS) (public * * * Internet file system), while port 445 and port 139 are mixed.
It is the main channel for ransomware intrusion. With it, we can easily access all kinds of * * * folders or * * * printers in the LAN, but it is precisely because of this.
Hackers have an opportunity, they can secretly enjoy your hard disk through this port, and even format your hard disk silently! What we can do is to find ways to prevent hackers from taking advantage of it and plug the 445 port vulnerability.