This paper discussed about various ways of computer virus and worm propagation techniques with the help of slammer and blaster worms case studies. A polymorphic worm is an upcoming technique which is a huge threat to the internet community. Few computer worms are written in a way that can be affected only to a particular region and attack at random times.  The big threat to the network and to the websites is created by these worms and that big threat is termed as Distributed Denial of Service (DDoS).

Overview:

Computer virus is the most high profile threat to information integrity.  Attackers over the network always attack the computers to exhaust important resources, damage the data and create havoc over the network.  Computer viruses had more visibility with the growth of global computing.  Computer viruses and computer worms are increasing rapidly day by day.  So, there is a need to create awareness among the people about the attacks of Computer viruses and worms.  Frequently, viruses require a host, and their target is to infect other files to live longer. A virus might rapidly infect every file or slowly infects the documents on the computer.  The computer worm is a program which designed in a way to copy itself from one computer to another, by using some network medium like e-mail, TCP/IP.  Unlike computer virus, worm is interested in infecting machines over the network. 

The prototypical worm infects target system only once then it tries spread to other machines over the network. Mailers and Mass-Mailer worms, Octopus and Rabbits are few of the categories come under computer worms. A Trojan Horse pretends to be useful programs but performs some unwanted action. Apart from Viruses, Worms and Trojan Horses, the other types of malicious programs are Logic Bombs, Germs, and Exploits. 

Conclusions:

This paper discussed about various computer viruses, worms and different malicious code environments. Attackers can get good control on internet hosts and also has the capability to spread their virus over network in few minutes which causes risk to the security of internet. 

Download  CSE Seminar Report on Study of Viruses and Worms .