Welcome To

The Virus World

Presentation

Explorer Virus

SICK OF COMPUTER VIRUSES?

What they are…Where they come from…Why they are here…

INDEX

History

Concept

Symptoms

Types Of Infections

Types Of Viruses

Conclusion

HISTORY The first computer virus was called

“Creeper.”It was invented in the early 1970’s.Since then, millions of viruses have been invented.

The first known computer virus was written in 1981 by a man named Rich Skrenta . This virus was termed Elk Cloner, and was the first computer virus to appear outside the computer where it was created in.

Everyone who owes a computer might heard a lot about computer viruses….

WHAT IS A COMPUTER VIRUS?

• A Computer Virus is a program that can copy itself and infect a computer without the permission or knowledge of the user.

• A Computer Virus has 2 major characteristics: the ability to replicate itself, and the ability to attach itself to another computer file...

SYMPTOMSThe following are a few Symptoms that your computer might have a virus:• Slow response and slow program execution.• Random hard drive crashes and restarts.• Distorted graphics and text.• Files that have mysteriously vanished.• Extensive pop-up ads.• Inability to open files with existing passwords.

TYPES OF INFECTIONS

Viruses

Malware

Worms

Trojan-Horses

TYPES OF COMPUTER VIRUSES

1. Boot Sector Virus.

2. Direct Action Virus.

3. File Infector Virus.

4. Macro Virus.

5. Multipartite Virus.

6. Polymorphic Virus.

7. Resident Virus.

8. Web Scripting Virus.

BOOT SECTOR VIRUS

It places its own codesand commands into MBR.

BROWSER HIJACKER

Alters the search and error page of a browser and redirectsthe user to its own page.

DIRECT ACTION VIRUS

•They load with the host program into computer’s memory.

•They can be crafted with relative ease.

FILE INFECTOR VIRUS

•A file infector is a virus that infects an executable file.

•Typically affects only one type of file.

MACRO VIRUS

•These type of virus infects word , excel, PowerPoint, access and other data files. Once infected repairing of these files is very much difficult.

MULTIPARTITE VIRUS

May attack in more than one methods.

POLYMORPHIC VIRUS

A virus that can encrypt its code in different ways so that it appears differently in each infection. These viruses are more difficult to detect.

RESIDENT VIRUS

• Hides within the computers memory.• It activates whenever the OS loads or

operates.• This virus may be pernicious.• It is of 2 types: Fast Infector. Slow Infector.• Removal of this virus is bit tricky.• It may be designed to block the

actions of Anti Virus programs.

WEB SCRIPTING VIRUS

There are few website that execute complex code with the purpose to provide interesting content ,these codes often get exploited and due to this a virus becomes able to infect a machine and to take actions on a machine via website. This particular virus is called web scripting virus

LATEST VIRUSES

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REVETON

CRYPTOLOCKER

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