Lesson 17 Introduction computer threats

the computer is great tool store important information. in certain cases, the information is very vital that losing it will harm the computer system.

computer threats can come from many ways either from from human or natural disasters. for example,when someone is stealing your account informationfrom a trusted bank, this threat is considered as a human threat. however, when your computer is soaked in heavy rain, then that is a natural disaster threat.

malicious code is also known as a rogue program. it is a threat to computing assets by causing undesiredeffect in the programmer's part. the effect is cause damage.

the agent for malicious code is the writer of the code,or any person who causes its distribution. There are various kinds of malicious code. they include virus horse, logic door,trapdoor and backdoor,worm and many others.

MALICIUOS CODE

a) Virus

• a program that can pass on the malicious code to other programs by modifying them
• attached itselft to the program, usually files with .doc,xls and exe extentions
• destroys or co-exists with the program
• can overtake the entore computing system and spread to other systems

b) trojan horse

• a progam which can perform useful and unexpected action
• must be installed by users or intruders before it can affect the systems assets
• an example of a trojan horse is the logic script that requests for users login ID and password
• the information is then used for maliciuos purpose

c) Logic Bomb

• logic bomb ia a malicious code that goes off when a spesific condition occurs
• an example of alogic bomb is the time bomb
• it goes off and causes threats at a specified time or date

d) Trapdoor or backdoor

• a features in a program that allows someone to access the program with special privileges

e) Worm

• a program that copies and spreads itself through a network

Primary different between worms and viruses

HACKER

hacking is a source of threat to security in computer. It is define as unauthorised access to the computer system by a hacker.

Hackers are person who learn about the computer system in detail. They write program referred to as hacks. Hackers may use a modem or cable to hack the targeted computers.

NATURAL AND ENVIRONMENTAL THREATS
Computers are also threatened by natural or enviromental disaster. Be it at home,stores, offices and also automobile. Examples of natural and environment disasters:

• flood
• fire
• earthquakes, storm and tornado
• excessive heat
• inadequate power supply

THEFT

Two type of computer theft
1. Computer is use to steal money, information and resources
2. Stealing of computer especialy notebook and PDAs

Three approached to prevent theft
1. prevent access byusing locks, amart card or password
2. prevent porbtability by restricting the hardware from being moved
3. detect and guard all exits and record any hardware transported