This document defines and describes different types of malware. Malware refers to hostile or intrusive software like viruses, worms, Trojan horses, spyware, and more. Malware is used to disrupt computers, gather sensitive information, or gain unauthorized access. Viruses spread by infecting executable files and programs and require user intervention, while worms actively transmit themselves over networks without human involvement. Common goals of malware include stealing personal data like social security numbers or taking control of computers to send spam or launch denial of service attacks. Protecting against malware involves understanding how different types like viruses and worms operate and spread.

1. MALWARES

2. • 'Malware' is in general used to refer to a variety
of forms of hostile or intrusive software.
• Malware is used or created to disrupt computer
operation, gather sensitive information, or gain
access to private computer systems.
• Malwares appear in form of code, scripts, active
content, and other software.
• Malware harm a computer’s system, data &
performance.

3. • Malware is often used against individuals to gain
personal information such as social security
numbers, bank or credit card numbers.
• The majority of widespread malware have been
designed to take control of user’s computers.
• Infected “Zombie Computers" are used to
send email spam, or to engage in Distributed
Denial Of Service Attacks [DDOS].
• Nature of Malware : Infectious, Concealment.

4. Types of Malware-
• Viruses
• Worms
• Trojan Horses
• Spyware
• Adware
• Rootkits
• Backdoors

5. VIRUSES
• The term ‘computer virus’ is used for a program
that has infected some executable software
and, when run, causes the virus to spread to
other executables.
• Any virus will by definition make unauthorized
changes to a computer, which is undesirable
even if no damage is done or intended.
• A virus requires user intervention to spread.

6. • Infections are transmitted by email or Microsoft
Word documents, which rely on the recipient
opening a file or email to infect the system.
• Many viruses attach themselves to executable files
that may be part of legitimate program.
• If a user attempts to launch an infected program, the
virus code may be executed simultaneously.
• For example, an executable may be created named
"picture.png.exe", in which the user sees only
"picture.png" and therefore assumes that this file is
an image and most likely is safe, yet when opened
runs the executable on the client machine.

7. A Few Types Of Viruses-
• Boot Sector Virus
• Macro Virus
• Polymorphic Virus
• Logic Bombs/Time Bombs.

8. WORMS
• A worm is a program that makes and facilitates the
distribution of copies of itself; for example, from one
disk drive to another, or by copying itself using email
or another transport mechanism.
• It actively transmits itself over a network to infect
other computers.
• It may arrive via exploitation of a system
vulnerability or by clicking on an infected e-mail.
• A worm can exploit security vulnerabilities to spread
itself automatically to other computers through
networks without any human intervention.

9. NEXT SESSION
• Trojan Horses
• Spyware
• Adware
• Rootkits
• Backdoors
And…….

10. • How computer viruses are spread
• Ways to safeguard our system & prevent
computer viruses…..

11. THANK YOU