Computer Viruses

COMPUTER VIRUS BY : PRIYANKA GUPTA

N O I T C U D O R T IN TO

INTRODUCTION Virus are basically something which

makes your pc works against your will. That is , your pc starts working differently.

IS VIRUS GOOD FOR MY COMPUTER?????

Absolutely! If you want to get rid of all that data clogging up your hard drive, a virus is a wonderful solution. If you want your spanking new computer to slow down to a crawl, then a virus is the way to go. If you're lucky, you may even get a worm which will not only help you clean up your computer from all those annoying files, but will also send a copy of itself to all your

In short, if you think that your computer

is too fast and gives you too little trouble, a virus or two can really help! Thankfully, you don't have to try too hard to get a virus. Simply connect an unprotected computer to the Internet for a few hours and let them come. That's all it takes.

Computer viruses are called viruses because

they share some of the traits of biological viruses. A computer virus passes from computer to computer like a biological virus passes from person to person

HOW ITS GET INTO YOUR PC???

The person read email at their PC or if they use

diskettes to transfer files between the computer at work and the computer at home, or if they just transfer files between the two computers they have a good possibility to get a virus. They might get viruses also when they download files from any internet site.

? ? ? ? E R A W L A M S I T A H W

MALWARE MALWARE IS A GENERAL TERM FOR ALL HARMFUL

PROGRAMS : VIRUS WORMS TROJAN HORSE

VIRUS MALWARE

TROJAN HORSE

WORMS

WHAT IS A VIRUS ?????

A computer virus is a program, a block of

executable code, which attach itself to, overwrite or otherwise replace another program in order to reproduce itself without a knowledge of a PC user. A true virus can only spread from one computer to

another (in some form of executable code).

EXAMPLES--It all started in 1999 when Melissa virus infected

over 100,000 computers. The LoveLetter virus caused damages of more than $8 billion in 2000. The history of computer viruses dates back to 1986. Computer viruses used to spread by disk. But as the Internet became popular, viruses started spreading faster by e-mail

TYPES OF VIRUSES Resident viruses Overwrite viruses Boot viruses Macro viruses Directory viruses Logic bomb FAT viruses, etc.

Many programs, multimedia or other goodies can

be found on the Internet. Often they are free and, let's face it, there are very few things that people like more than free stuff. The trouble with some free software is that it also comes with one or more viruses already included free of charge. Hence the name "Trojan Horse".

WHAT IS TROJAN HORSE????

TROJAN HORSE A TROJAN HORSE is a computer program, a

program that claims to do one thing (it may claim to be a game) But instead does damage when you run it (it may erase your hard disk) TROJAN HORSES have no way to replicate automatically.

They require interaction with a hacker to

fulfill their purpose. The hacker need not be the individual responsible for distributing the Trojan horse. It is possible for hackers to scan computers on a network using a port scanner in the hope of finding one with a Trojan horse installed. .

WHAT IS WORM????

WORMS A WORM is a small piece of software that uses

computer networks and security holes to replicate itself. A copy of the worm scans the network for another machine that has a specific security hole. It copies itself to the new machine and starts replicating from there.

EXAMPLE --mydoom worm morris worm was the first worm discovered

released in 2 Nov,1988.

End users may be tricked into running the worm

program when they receive it via a network e.g by double clicking on an executable file attached to email. In 2003 the Slammer Worm almost brought the entire Internet down.

HOW VIRUS SPREAD

?????

Basically it gets spreadWhen the infected program is distributed byFloppy disk Uploaded to a bulletin board Zipped and delivered as an executable then other programs get infected and this is how viruses spread.

VIRUS ATTACKS

Some sort of trigger will activate the attack

phase, and the virus will then “do something”. Anything from printing a silly message on the screen to erasing all of your data. The trigger might be a specific date ,or the no. of times the virus has been replicated or something similar.

Load viruses into memory so they run in the

background Infect the boot sector on floppy disk and hard

disks.

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

With E-mail viruses

Never double-click on an attachment that Contains an executable program. Attachments that come in as Word files(.DOC) ,images(.GIF and . . . JPG) , etc. are data files . And they can do no damage. A file with an extension like . EXE , .COM , or .VBS is an executable and can do all sorts of damage

TOP 5 ANTIVIRUS Bit Defender Antivirus Kaspersky Antivirus Web root Antivirus G-Data Antivirus ESET Nod 32

(according to software review top ten views)

CON

N O I S U L C

Though there is nothing to tense if your system

have viruses. But ,you shouldn’t neglect the virus threat. There are quite a few dangerous viruses roaming the Internet. So keep your hard drive happy and don't let the viruses ruin your day. Here is what you can do: 1)Make sure your computer runs anti-virus software. If not, buy and install it immediately.

Even if you have this software, it must be

updated regularly, as new viruses appear daily. Configure the programs to automatically download updates, making it easy to stay protected. Otherwise, periodically download the updates manually.

 DO NOT OPEN an e-mail attachment unless

you know who sent it. Even then, it's not totally safe, as a sneaky virus that has infected a friend's computer can access the e-mail address book, send a message to everyone, and attach itself. To be completely safe, scan the attachment with your anti-virus software BEFORE you open it.

If you receive a suspicious message, delete it

immediately from your Inbox. When you delete a message, however, it's still on your system. Go into the Deleted Mail folder and delete the message again to permanently remove it from your computer. Regularly back up your files. Should your

system become infected, you won't lose valuable data.

! ! ! ! ! ! U O Y K N A TH