Hackers with advanced knowledge try to find vulnerabilities in some services, programs or processes used by operating systems and concentrate their attacks on these points. Thanks to the notifications received from the users and the experts it contains, Microsoft company, which has been successful in detecting the vulnerabilities of the system and closing them, offers operating system updates free of charge. Finding a security vulnerability in an operating system that is kept up-to-date using the automatic update function is difficult for an attacker.
Another form of attack is based on finding security gaps by browsing on computers connected to the Internet. The network protocol on which the Internet is built is the TCP / IP (Transmission Control Protocol / Internet Protocol) protocol suite. According to the OSI (Open Systems Interconnect) model, we can say that this protocol consists of 7 layers, and the network traffic can be directed and controlled thanks to the ports in the Transport layer. According to this system, certain operating system programs, services and network services communicate via their own connection points (eg TCP 80 for Http, UDP 53 for DNS, TCP 3389 for Terminal Services, TCP and UDP 2178 for Background Intelligent Transfer Service, etc.). . Thus, connection points of well-known services can become the target of attackers.
Usually, the most effective way to eliminate these threats that arise as a result of the attacks carried out by attackers who are connected to the Internet randomly or according to certain IP ranges is to use a hardware or software firewall solution. In many cases, it is seen that both species are used together.