Introduction
In the previous chapter, we focused on penetration testing the target operating system. Operating systems are the first level of penetrating the target because an unpatched and outdated operating system can be easy to exploit and it will reduce our effort of looking for other methods of penetrating the target. But the situation can vary. There can be cases in which a firewall may block our scan packets and, thus, prevent us from gaining any information about the target operating system or open ports.
There can also be a possibility that the target has automatic updates which patches the vulnerabilities of the operating system at regular intervals. This can again kill all the attacks of penetrating the target. Such security measures can prevent us from gaining access to the target machine by exploiting known vulnerabilities of the operating system in use. So we will have to move a step ahead. This is where client-side exploitation and antivirus bypassing techniques comes into...
