Computer virus and worms

1. Presented by
Rishi Ram Khanal
BIM 6th (108) (TU)
Computer virus and worms
11/27/20201

2. Look ahead
 Introduction
 Types of virus
 How virus are active
 Computer worm
 Characteristics of warm
 Phases of warm and virus
 Virus vs warm
 conclusion
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3. WHAT IS COMPUTER VIRUS
 Computer viruses are small software programs that
are designed to spread from one computer to another
and to interfere with computer operation.
 A virus might corrupt or delete data on your
computer, use your e-mail program to spread itself to
other computers,
 or even erase everything on your hard disk.
 Viruses are most easily spread by attachments in e-
mail messages or instant messaging messages.
 That is why it is essential that you never open e-mail
attachments unless you know who it's from and you
are expecting it.
 Viruses can be disguised as attachments of funny
images, greeting cards, or audio and video files11/27/20203

4. OTHER TYPES OF VIRUS
 Bacteria
Bacteria, also known as rabbits, are programs that
do not directly damage the system.
 Bombs
A bomb is actually a type of Trojan horse that can
be used to release a virus or bacteria.
 Salami
Salam is cut away tiny pieces of data. They can be
particularly dangerous as the damage they do is
small and can be attributed to some truncation of
the system.
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5. HOW VIRUSES ACTIVE
 We are always afraid that viruses do something
harmful to files when they get active, but not all
the viruses activate.
 Some viruses viruses just spread out, but when
viruses activate they do very different things..
Might play a part of melody or play music in the
background, show a picture or animated picture,
show text, format hard disk or do changes to files.
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6. COMPUTER WORMS
 A worm is a program that uses computer
networks and security holes to replicate itself.
 Scans the network for another machine that has a
specific security hole and copies itself
 Use up computer processing time and network
bandwidth during replication.
 Carry payloads that do considerable damage.
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7. Characteristics of a Worm
 Enhanced Targeting
 Enhanced Speed
 Enhanced Capabilities
 Enhanced Destructive Power
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8. Phases of a worm or virus operation
 Dormant Phase
 Propagation Phase
 Triggering Phase
 Execution Phase
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9. 11/27/20209

10. Protecting your Computer
System
 ensure that your OS is up-to-date
 To have antivirus software and make sure it has
the capability to scan e-mail and files as they are
download from the internet
 Need to run full disk scans periodically
 Use a Firewall
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11. Thank you
Any question ?
11/27/202011