1. By: Angelica Jurczak Anna Rog David Brackett
Computer Viruses
By: Angelica Jurczak
Anna Rog
David Brackett

2. What is a Computer Virus?
A computer virus is a computer program that can copy itself and infect a computer without the permission or knowledge of the owner.
One of the first detected virus was the Creeper virus in the early 70’s
Before computer networks became widespread, most viruses spread on removable media, particularly floppy disk.

3. Basic Computer Viruses
Trojan Horses
appears as interesting program file but when installed it allows intruders to access and read your files
Worms
virus that copies and multiplies itself by using computer networks and security flaws
Viruses
use messages to spread which allow it to automatically forward itself to thousands of people

4. Types of Viruses Boot Sector Virus Program Virus Multipartite Virus
Infects the boot or MBR of diskettes and hard drives through the sharing of infected disks and pirated software applications
Once your hard drive is infected all diskettes that you use in your computer will be infected
Program Virus
Becomes active when the program file (usually with extensions .BIN, .COM, .EXE, .OVL, .DRV) carrying the virus is opened
It then makes copies of itself and will infect other programs on the computer
Multipartite Virus
Hybrid of a Boot Sector and Program viruses
It infects program files and when the infected program is active it will affect the boot record

5. Types of Viruses Stealth Virus Polymorphic Virus Macro Virus
Disguises itself to prevent from being detected by antivirus software
It alters its file size or conceals itself in memory
Polymorphic Virus
Act like a chameleon, changing its virus signature (binary pattern) every time it multiples and infects a new file
Macro Virus
Programmed as a macro embedded in a document, usually found in Microsoft Word and Excel
Once it gets in to your computer, every document you produce will become infected
Relatively new type of virus and may slip by your antivirus software if you don't have the most recent version installed

6. Signs Your Computer is Infected
Functions slower than normal
Responds slowly and freezes often
Restarts itself often
See uncommon error messages, distorted menus, and dialog boxes
Notice applications fail to work correctly
Fail to print correctly

7. Computer Virus History

8. First half of the 70'Late 60,s, early 70,s- "Rabbits" cloned themselves occupied system resources, slowing down the productivity. 
-"The Creeper"  capable of entering a network by itself and transferring a copy of itself to the system.
Early 80,s-Increasing number of programs written by individuals not by software companies. Programs caused miner viruses called "Trojan horses".
1986'Brain virus' - by Amjad and Basit Farooq Alvi.
spread through floppy disks,
infected boot records and not computer hard drives
Lahore, Pakistani Brain, Brain-A and UIUC virus
-took over free space on the floppy disk and hid from detection ”disguised itself by displaying the uninfected boot sector on the disk.”
1987-Lehigh virus
- the first memory resident file infector that attacked executable files and took control when a file was opened
The Jerusalem Virus
-had bugs that re-infected programs that were already infected

9. 1988: Robert Morris made a worm that invaded ARPANET computers
disabled 6,000 computers on the network by overflowing their memory banks with copies of itself
1991: Norton Anti-Virus software
1999: "Melissa" virus
-infected thousands of computers very fast by sending copies of itself to 50 names in the address book on Outlook
Led to an estimated $80 million in damage and record sales of anti-virus products.
2000: "I Love You" virus
-was sent by and infected 10 % of computers in only one day
-created by a young Filipino computer student who did not get punished because then the Philippines had no laws against hacking which led to the European Union's global Cybercrime Treaty.
2001: "Nimda" virus (days after 9/11)
-had 5 ways of infecting systems

10. 2004
MyDoom spreads through s and file-sharing software faster than any previous virus or worm.
Allows hackers to access the hard drive of the infected computer.
An estimated one million computers running Windows are affected by the fast-spreading Sasser computer worm.
The worm does not cause irreparable harm to computers or data, but it does slow computers and cause some to quit or reboot without explanation.
2006
Discovery of the first-ever malware trojan horse for Mac OS X
2008
Torpig is a Trojan horse which affects Windows, turning off anti-virus applications.
It allows others to access the computer, modifies data, steals confidential information and installs malware on the victim's computer.
2009
Conficker infects anywhere from 9 to 15 million Microsoft server systems.
French air force, Royal Navy warships and submarines, Sheffield Hospital network, UK Ministry of Defence, German Bundeswehr and Norwegian Police were all affected.

11. Total Number of Viruses by year January January January January January January January ,161 January ,482 January ,687 January ,626 January ,764 January ,037 January ,726 January ,850 January ,000 January ,000 January ,000 January ,000

12. Melissa
Another virus that fired up the media was Melissa, a Word macro virus.
When people received the host Word document via and opened it, the virus sent a copy of itself to the first 50 people in the victim's address book.
Named after a topless dancer in Florida, the Melissa virus crashed the servers of corporations and governments in different spots around the world.
The Computer Emergency Response Team, set up after Robert Morris mucked up the Internet with his worm in 1988, estimated that the virus hit 100,000 computers in its first weekend.
David L. Smith posted the infected file to an alt.sex usenet group using a stolen AOL account. Initially he entered a plea of innocence, but after being confronted with a maximum sentence of 40 years in prison, he eventually pled guilty and received a much-reduced sentence.

13. Love You, Love Bug
By almost any measure, the so-called Love Bug was the most damaging and costly virus ever. I don't know who comes up with these whack figures, but according to Reuters the bug cost the world $15 billion in lost productivity.
The Love Bug spread far faster than Melissa. Unlike Melissa, it would mail itself to everyone in your Outlook address book -- most of whom would probably be delighted to read about how you love them -- not just the first fifty. Moreover, it would gobble up certain media files stored on your hard drive.

14. Did you know?
One German newspaper tragically lost 2,000 pictures from its archive.
The perpetrator turned out to be a 23-year-old Filipino computer science student who more or less plagiarized all of his code.
The lack of laws in the Philippines covering computer crimes, he pretty much got away with his crime.

15. Prevention Upload and use antivirus software
Be aware of the s and attachments you open
Check for updates on antivirus software regularly
Make sure antivirus software is installed correctly

16. Sources http://www.tech-faq.com/history-of-computer-viruses.shtml

17. References
Wikipedia