computer viruses
DESCRIPTION
UNIVERSITY OF SARGODHA, MANDI-BAHAUDDIN CAMPUSTRANSCRIPT
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UOS.MBD
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What is a Computer Virus ?
Computer virus refers to a program which damages computer systems and destroys or erases data files
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Who creates/writes viruses ?
INFO ATTACKERS
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Why people creates computer viruses?
To attack the products of specific companies.
To theft the confidential info. To distribute political messages.
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Virus codes can be written…… By using
Assembly languages like Basic, c,Pascal e.t.c
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What will happen if your computer
Infected by virusFunctions slower than
normalResponds slowly and
freezes oftenRestarts itself oftenSee uncommon error
messages, distorted menus, and dialog boxes
Notice applications fail to work correctly
Fail to print correctly
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MajorTypes of Viruses
Virus
Boot Sector Virus
Boot Sector Virus
Program/File
Infector
Program/File
Infector
TrojanHorsesTrojanHorses WormsWorms Macro
VirusesMacro Viruses Root KitRoot Kit
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The boot virus affects the
booting process of the
infected computer system.
thus causing slow start up
and shut down process
Boot Sector Virus
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Program/File Infector virus
Becomes active when the
program file carrying the
virus is opened.
usually with below extensions
.BIN .COM
.EXE .OVL
.DRV
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Appears as interesting
program file but when
installed it allows
intruders to access and
read your files
Trojan Horses
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Copies and multiplies it
self by using computer
networks and security
flaws
Worms
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Programmed as a macro
embedded in
a document, usually
found in Microsoft Word
and Excel.
Macro Virus
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Designed to take
fundamental control of
a computer system,
without authorization by
the system's owners
RootKit
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Sources of Viruses
Removable Data Storage Devises
Internet
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Virus Prevention
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Anti-Virus
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How does an Anti-Virus work ?
Scanner:
Detects the virus by using a list of existing virus
signature/definitions.
Monitors:
These are memory resident programs and alert
when any changes find in executable program.
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Better than
Conclusion
Prevention is
Cure
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Thank you