Computer virus

2. Introduction
 Computer virus have become today’s
headline news.
 With the increasing use of the internet, it
has become easier for virus to spread.
 Virus show us loopholes in software.
 Most virus are targeted at the MS
Windows OS.

3. What is a Virus ?
 A virus is just a computer program. Like any
other program, it contains instructions that
tell your computer what to do.
 But unlike an application, a virus usually
tells your computer to do something you
don't want it to do, and it can usually spread
itself to other files on your computer -- and
other people's computers.

4.  In some cases, a virus will execute only a
gentle "personality quirk," such as causing
your computer to make seemingly random
bleeps.
 But a virus can be very destructive; it could
format your hard drive, overwrite your hard
drive boot sector, or delete files and render
your machine inoperable.

5. History of Viruses
 As time progressed many other types of viruses
were developed.
 In 1992, four students at Cornell University
created the MBDF virus.
 This virus attacked Apple Macintosh
computers.
 The virus was released in three shareware
programs: Obnoxious Tetris (computer game),
Ten Tile Puzzle (computer game), and Tetris
cycle (Trojan Horse program).
 This virus was benign, but the perpetrators
were severely punished.

6. General virus types
 Boot Sector Virus
 Macro Virus
 Multipartite Virus
 Polymorphic Virus
 Worms
 Trojan horses
 E-mail viruses
 Stealth Virus

7. How They Spread ?
 Early viruses were pieces of code attached to
a common program like a popular game or a
popular word processor.
 A person might download an infected game
from the internet or copy it from a floppy
disk and run it.
 A virus like this is a small piece of code
embedded in a larger, legitimate program.
Any virus is designed to run first when the
legitimate program gets executed.

8.  If one of the infected programs is given to
another person on a floppy disk, or if it is
uploaded to internet, then other programs get
infected.
 This is how the virus spreads.

9. The impact of viruses
 ICSA Labs estimates that the cost of a
virus disaster is between $50,000 and
$500,000
 Average server downtime for a virus
is 14 hours

10. The impact of viruses

11. Examples of risky file types
 The following file types should never be
opened:
 .EXE
 .PIF
 .BAT
 .VBS
 .COM

12. TOP 5 Viruses Reported
14
12
10
8
6
4
2
0
W32/klez/h W32-
Bugbear-A
Percent Reported to
Sophos 2003
W32/ElKern-
C

13. Symptoms of Virus Attack
 Computer no longer boots up.
 Screen sometimes flicker.
 Computer runs slower then usual.
 PC speaker beeps periodically.
 System crashes for no reason.
 Files/directories sometimes disappear.
 Denial of service (dos)….. & Many More.

14. Prevention is the best cure
 Run a secure operating system like
UNIX or Windows NT.
 Install virus protection software.
 Avoid programs from unknown
sources.
 Disable floppy disk booting

15.  Macro Virus Protection is enabled in all
Microsoft applications.
 Never double-click on an attachment that
contains an executable that arrives as an
e-mail attachment.

16. Protect Yourself from Computer Viruses
 AVIEN & AVI-EWS
 CERT
 STOPzilla
 GFI Mail Security for
Exchange
 Anti Virus eScan 2003
 CIAC
 Cyber notes
 ICSA
 Information Security
Magazine
 NIPC (National
Infrastructure Protection
Ctr)
 SANS Institute
 Virus Bulletin

17. How To Scan?

18. Anti-Virus Is Scanning

19. Finding Out A Virus

20. Top 9 Virus Protectors are...
1) PANDA ANTIVIRUS PLATIINUM v7.0
2) NORTON ANTIVIRUS 2003
3) F-PROT FOR WINDOWS
4) MCAFEE VIRUSSCAN HOME EDITION
7.0
5) NORMAN VIRUS CONTROL
6) PC-CILLIN
7) BIT DEFENDER PROFESSIONAL v6.5
8) NOD 32
9) STOPzilla!