2ThreatsA computer virus is a computer program that invades your computer system without your knowledge and consentIt hides itself while doing its work.Frequently s attachments spread viruses
3Basic Characteristics It is able to duplicate itself:It could replicate orattach itself to a file which when shared will infect the next computer.It is able to hide and protect itselfIt must have a PAYLOAD.
4Types of threats Trojan Horse Boot Sector Virus File Virus Worms Time BombsMacro Viruses
5Trojan Horse This often comes as an appealing attachment While you are busy with the game the virus infects your system.These files could lead to data theft
6Boot Sector Virus The boot sector contains vital data for a computer. It is one of the first things looked at when you switch on.This virus could put the boot sector somewhere else.
7File VirusThis will attach itself to any program i.e. any file with the extensionEXE orCOM.It can be carried to another system via a USB
8WormA worm will replicate themselves until all available locations on the hard drive are full causing the system to crash.
9Time bombThese programs lurk in your system, infecting all disks and other computers on a network. They wait for a specific time or event to do whatever job they have been programmed to do.
10Macro Virus These viruses infect Microsoft application files. They attach themselves to a documentThe document enters the system as a macro.A macro is a program a collection of words, phrases or commands that can be activated by a simple action like a combination of two key presses.When the next clean document is worked with, the macro attaches itself to the new document to go and infect another computer.
11Benign or malignant? Benign Malignant When activated does something harmless but irritatingWhen it has stopped running you are given control of your computer again.Generally written as jokesMalignantWritten to cause damage to filesIt can replicate rapidly and infect data and program files within minutes of entering your system.
12Who Writes a Virus? Malicious people who have some sort of grudge. Bored students who need something to stimulate their creative powers.Pranksters who think it is amusing.
13Damage Caused by a Virus It can cause damage any file on your hard drive or memory stick e.g. drivers.BusinessesClearing up is time-consuming and costly.It requires the services of a specialist in the field.Essential data could be lostHomeLoss of dataInconvenience because you may have to reformat your hard drive.
14Infection rateA virus can transfer copies of itself dozens of times in a matter of seconds.In the workplace, computers are usually networked.If a computer is infected every machine in the company could be infected almost instantly.If each worker takes an infected USB home, each home machine becomes infected.If each spouse takes an infected USB to work and if each child takes an infected USB to school you will have a pandemic.
15Does your computer have a virus? Strange messages or graphics appear on your monitor.Sounds that are not part of your program could be played.Your hard disk could reformat itself without you having given the reformat command.Unknown files or directories are created.Files expand in size for no known reason.Files are corrupted.Your computer starts to work slowly.The computer is unable to boot up because the boot sector has been relocated.The FAT has been moved and it appears that you have no files on your disk.
16Cleaning an infectionReformatting the hard drive is extreme but undesirableUse an inoculation programs.These programs find the virus and destroy or quarantine it.They may try to patch the damageThey can fix a known virus they cannot fix a virus that is still to be written.
17What are virus definitions? These define what a virus is and what it can do. When a company finds a new virus they get into the program code and look for the defining part of the virus. They write code to defuse or destroy the virus.
18Update your virus definitions The fact that the old viruses can be treated is a stimulus to their authors.You can almost hear them saying “They found that one! Let’s see how long it takes them to crack this new one!” and out will pop a new virus.This is then analysed by the anti virus companies until they find the program that will crack that new virus and so the vicious circle starts again!
19How to Prevent Infection Only use new software bought from a reputable agent.Isolate your machine if you can!Ensure that a computer is clean before you use your USBInstall a virus checker in your home computer and convince your company and friends to do the same.Update your virus checker’s data base regularly.Download files from reputable sites on the Internet.Don’t boot with a USB in place.Change your CMOS setting so that drive C is the first drive it examines on boot-up.Scan all disks with your virus checking software before using them.Don’t open attachments from a strange source.
20HoaxYou will often receive an warning you not to open an with a particular subject line because it is a virus. Most of these are a hoax. Hoaxes cause panic and flood inboxes throughout the world. Before sending these warnings check on the Internet.
21SpamThis is unsolicited . In businesses it clutters up the inbox and uses space on the server. You can build in a filter that will delete all from a particular person as soon as it is received.
22PhishingWhen someone wants to gain access to your private details like passwords or bank details, they will use bait in the form of an or text message hoping to catch the “phish” – you!They could be attractive offers (“You have won £500,000 in the UK Lottery. Send us your details so that we can transfer the money to your account”) orCould cause you alarm (“We have noticed some unusual activity on credit card. Click here so that we can verify your details.”).Keyloggers are programs that capture all keystrokes as you type in the hopes that soon a password will be entered.The “Phisher” has access to your computer through this program and will patiently wait until he can pick up personal details.
23spoofingMost of us will open a friend’s . spoofing relies on this.spoofing is often used to gain access to certain details that could be used in Spam or in Phishing.
24PharmingPharming is an attempt by a hacker to block a legitimate web site. The people who type in the web address of this site will be redirected to a false web site. One of the main purposes of pharming is to assist in identity theft particularly if an on-line banking site is affected.
25Some other threats Twishing Phishing using Twitter Smishing Phishing using an SMSVishingPhishing using VOIP