3. GROUP MEMBERS (group # 9)
■ Alishba Ijaz Roll # 1721110003
■ Aqsa Shahid Roll # 1721110006
■ Zartash Jamil Roll # 1721110082
■ Noor Khalil Roll # 1721110051
4. Contents:
■ INTRODUCTION
■ History of Computer Virus
■ Similarities b/w biological and computer virus
■ How Does A Virus Work?
■ Life Cycle Of Computer Virus
■ Functional Diagram of VIRUS
■ Types of VIRUS
■ Methods of detecting Virus By ANTI-VIRUS
■ Prevention
5. Virus
V I R U S
VITAL
INFORMATION
RESOURC
E
UNDER
SIEGE(SLANG)
A VIRUS is ILLEGAL Computer Code that can do
such things as alter programs or destroy data. Also,
the virus can copy itself onto programs, thereby
spreading its damaging effects.
7. John Von Neumann:
Fred Cohen:
CORE WARS:
He came up with the theory about self-Replicating programs.
He came up with the term COMPUTER VIRUS.
An Application not release until 1984.
It Replicates itself every single time it was Run in Computer.
8. Reapers:
MS-DOS:
Morris Worms:
Antivirus application specifically designed to destroy core wars of an
infected Computers.
Most popular OS when viruses becoming thick and fast.
The most targeted OS by “THE BRAIN” Virus which release in
Pakistan in 1986.
Created by ROBERT MORRIS,23,a small virus that infected almost
6,000 computers.
9. Melissa Virus:
I Love You Virus:
Code Red Virus:
It managed to infect thousands of computers at an alarming
speed, causing over $80 million in damages.
It managed to infect millions of computers in just a day.
The virus sent usernames and passwords it found on the
infected computer back to the author.
It infected over 700,000 of computers, causing damages in excess of
$2 billion.
10. IN 2004:
No more notable
viruses appeared
due to
sophisticated
antivirus and
firewall system.
11. Similarities b/w biological & computer
virus:
Computer virus are called viruses because they share some of the traits of biological
Viruses. A computer virus passed from computer to computer like a biological virus
Passes from person to person.
Need a host for residence.
Capable of self-replicate.
Cause damage to host.
12. How Does A VIRUS Spread?
• First, the virus is linked to the host object in such a way that it
activates when the host object is used.
• Second, virus looks for other suitable carrier objects and attaches
itself to them.
• With this dependency virus slows down the system.
13. A typical lifecycle of a computer Virus:
The virus waits until user transmits the
infected object to another computer.
User transmits an infected object to another
computer.
The virus locates and infects suitable objects
on the new computer.
15. MACRO VIRUS:
BOOT SECTOR VIRUS:
A macro virus is associated with application
Software like WORD and EXCEL. When opening
the infected document, macro virus is loaded into
main memory and destroys the data stored in
hard disk.
A boot sector virus infects boot sector of the
computers. During system boot, boot sector virus
is load into main memory and destroys data
stored in hard disk.
16. WORMS:
Types of Worms Virus:
A worm is also a destructive program that fills a computer system
with Self-Replicating information.
MAIL WORMS
PURE WORMS
17. TROJAN HORSE:
LOGICAL BOMBS:
Trojan Horse is a destructive program. It
usually pretends as computer games or
application software. If executed, computer
system will be damaged.
A logical bomb is a destructive
program that performs an activity
when a certain action has
occurred.
19. Methods Of Detecting The Virus By Anti-
Virus:
• Signature Based Detection :
Compare the contents of a file to a dictionary of virus.
DATA BASE
-- - - - - - - - - - -
- - - - - -- - - - - -
- - - - - - - -- - - -
-- - -- - - - - - - - -
- - - -
101010
- - - - - - - - - - -
-
111001
- - - - - - -
101010
101110
- - - - - - -
101101
- - - - - - -
SAFE VIRUS
SAFE SAFE
20. Behavior based Detection:
• Observe how the program execute in the
computer
Rather than looking for signature.
• Check the suspicious file and show
warnings to the User.
21. PREVENTION:
Do not share Drive C: without a
password and without read-only
restrictions.
Use Anti-Virus.
Delete e-mail file attachments.
Have multiple backups of
important files.
More secure operating systems
e.g. UNIX
