Viruses, Worms & Trojan Horses

What Are viruses?

• They are programs which can destroy or cause damage to data stored on a computer system and to the computer itself!

• Virus program must be executed in order to infect a computer system. Viruses can attach themselves to other programs in order to ensure that this happens.

Common Symptoms of Virus Infections

• Displaying unwanted messages

• Unusual visual or SFX (sound effects)

• Loss of Data from a storage medium

• Computers restarting unexpectedly

• Unwanted generation of emails

Viruses can ...

• Corrupt or delete data • Disable the computer by

changing the operating system

• Cause silly messages to be displayed or sounds to be produced

• Use your computer to ATTACK other computer by generating spam (junk

emails) or overloading a company website with data.

WORMS

• Worms operate differently to viruses

• Worms can spread themselves to other computers without needing to be transferred as part of a host program.

• The first time a user may notice the presence of a worm is when the computers memory UNEXPECTEDLY fills up

Example of an email worms…

• Mimail.I and Mimail.F are email worms disguise themselves as an email from the PayPal on-line payment service and try to steal credit cards info.

• This method of fraud is known phishing

TROJAN HORSES • Trojan horse, also known as

Trojan, describes a list of computer threats (malware) that appear to perform good functions, but actually performs malicious functions that allow unauthorized access to the hosting machine

• FOR EXAMPLE – If a program is designed in such a way, it could open a gateway for hackers to control and attack the computer of the user, then that program is said to be a Trojan horse

THATS WHAT A REAL TROJAN HORSE LOOKS LIKE!

THANKS FOR WATCHING

By Jamil Tariq , Mariya Rasul and

Lisa Robertson

Jacqui Crooks Best teacher ever!!!!!!!! (L)