_Computer_Virus_The_things_u_must_know_

8/7/2019 _Computer_Virus_The_things_u_must_know_

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Introduction

About Virus

Computer virus have become

todays headline news.

With the increasing use of theinternet, it has become easier forvirus to spread.

Virus show us loopholes insoftware.

Most virus are targeted at the MSWindows OS


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~ ClassifyingComputer Virus ~

Aprogram designed toattach itself to a file,

reproduce, and spread fromone file to another,destroying data, displayingan irritating message, orotherwise disrupting

computer operations.

File Virus: A computer virus thatinfects executable files, that isprograms with exe filenameextensions

Payload: The disruptiveinstructions or message deliveredby a computer virus. Payloadscan range from just being

annoying to destroying data andfiles on a computer system.

Boot Sector Virus: A computervirus that infects the sectors on adisk that contain the data acomputer uses during the bootprocess. The virus spreads everytime the infected disk is in thecomputer when it boots.

Macro Virus: A computer virusthat infects the macros that areattached to documents andspreadsheets.

Trojan Horse: A computerprogram that appears to perform

one function while actually doingsomething else, such as inserting


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* Virus through the

Internet*

Today almost 87% of all viruses

are spread through the internet.Transmission time to a new host

is relatively low, on the orderof hours to days

Latent virus


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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.


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~Computer Virus~

How They Spread A virus runs first when a legitimate

program is executed. The virus loads itself into memory

and looks to see if it can find anyother programs on the disk.

If it can find one, it modifies it to addthe virus's code to the new program.

Then the virus launches the "realprogram.

The user has no way to know thatthe virus ever ran.

Unfortunately, the virus has nowreproduced itself, so two programsare infected.

The next time either of thoseprograms gets executed, they infect

other programs, and the cyclecontinues.

When the infected programo is distributed by

floppy disk uploaded to a bulletin board

zipped and delivered as anexecutable.

then other programs get infected.


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~Computer Virus~How To Prevent Them

Security features keep viruses away. Buy virus protection software. Avoid programs from unknown sources (like

the Internet). Stick with commercial software purchased on

CDs.


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~Computer Virus~

How To Prevent Them With E-mail viruses

o defense is personal discipline Never double-click on an attachment that contains

an executable program Attachments that come in as

Word files (.DOC), spreadsheets (.XLS), images (.GIF and.JPG), etc., are data files

and they can do no damage


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Dont victimize yourselfo learn where to find legitimate information on

hoaxes, myths etc.

do not forward warnings if you havent personallychecked them out!


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~Computer Virus~

How To Prevent ThemDont fall for the

"False Authority Syndromeo Most people who claim to speak with authority

about computer viruses have little or no genuineexpertise. The person feels competent to discuss viruses because of

his job title, because of expertise in another computer field,

simply because he knows how to use a computer.


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E-mail is clearly the predominant vulnerabilitypoint for viruseso Current viruses are spread via security holes in

Microsoft Outlook and Outlook Express Free patches are available from Microsoft to address theseproblems many people are reluctant to apply them.

First, update your system with Windows Update

and Office Updateo or, buy a Mac Buy virus protection software


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~Computer Virus~How To Scan?


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~Computer Virus~Anti-Virus Is Scanning


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~Computer Virus~Finding Out A Virus


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Computer Virus

Acknowledgement My special thanks goes to Sri Supriyo Ghosh

(Dept. of BCA,Techno India, Sec. V) forhelping & suggesting me about different kindof computer viruses & their characteristics.


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Computer Virus

Be Original Kill Piracy.

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