Aim: Create A BAckdoor
printf("Logic puzzle\nselect option:\n1)Author\n2)About\n");
printf("Version .007 \n");
As soon as the victim run this program, nc starts listening in the background at port number 4889 with a shell on it.So its a example of a very simple backdoor/trojan that can give access of your computer to the attacker.
In order to prevent this attack use a good firewall.And also keep checking at regular interval that what ports are open in your system, if you find any skeptical thing then immediately close that one or try to find out what service is using it.
you can do this using netstat command.It is available in linux as well as on window operating system.
if you are on a window box run this command regularly
this will help you out in the hardening of your operating system.