Turn off Windows XP related ports to secure

Windows XP as a widely used system has now been "favored" by more and more attackers. Of course, the easiest way to prevent it is to install a network firewall, but what if we don't have a firewall? Turning off the useless ports in Windows XP can make the system much safer.

First, find out the port that is open.

Scan the port, and then find the vulnerability is the basic idea of ​​the attacker's invasion. It can be said that the more ports open on the machine, the greater the chance of an attacker invading, so we can improve the security of the computer by closing some ports we don't use.

How do you know which ports are open in our Windows XP? We can use the command "Netstat" to view the open ports in the system.

We need to use two parameters of this command: -a, -n. The parameter -a shows all current connections and listening ports, while the parameter -n displays the address and port number in numeric format (instead of trying to find the name), which can be used in combination: Netstatan (Figure 1), you can view the current The port is open.


Figure 1

With this command, if we find an abnormal port number is listening, you can go online to find the port number of the common Trojan, if you find a Trojan The port should be checked with the software that kills the Trojan.

Second, close the useless port

After knowing how to check the port status of the machine, the next question is which ports are required and which ports can be closed? This problem is a bit more complicated, because in addition to Windows XP's default open 135, 137, 138, 139 and 445, some network-related software needs to use some ports, the most commonly used such as QQ uses 4000 ports. Here I imagine the situation as the simplest: a computer that only needs to browse the web. So for this system, we configure it ourselves to improve security.

1. Close the port that the software opens. You can open the "Properties → Internet Protocol (TCP /IP) → Properties → Advanced → Options → TCP /IP Filter Properties" of the local connection, and then select "Allow Only" (Figure 2). Please note that if you find that a common network tool does not work, please find out which port it is on your host, and then add the corresponding port in "TCP/IP Filter".


Figure 2

2. Disable NetBIOS. Open the local connection "Properties → Internet Protocol (TCP /IP) → Properties → Advanced → WINS → disable NetBiOS on TCP /IP" (Figure 3). This closes ports 137, 138, and 139, preventing IPC$ intrusions.


Figure 3

3, open the network firewall that comes with Windows XP. Open the local connection "Properties → Advanced", after enabling the firewall, click Settings to set which services the system is open to close. In general, these services are not required. After closing these services, the ports involved in these services will not be easily opened.

4. Disable port 445. Add a DWord value named "SMBDeviceEnabled" to the registry "HKEY_LO-CAL_MacHINESYSTEMCurrentControlSetServi cesNetBTParameters" and set it to 0, just fine.

With the above settings, the security of your Windows XP system will be greatly improved. To add, the article is for machines that dial directly to the Internet, and does not include machines that go online through a gateway proxy.