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  • Home
  • 1 - Theory of Computer Science
  • 2 - Practical Problem Solving and Programming
  • Pre-Release Material
    • 2018 June >
      • 22 >
        • 22 - Cow Task
        • 22 - Task 1
        • 22 - Task 2
        • 22 - Task 3
  • 1 - Computer Systems (2023)
1 - Theory of Computer Science  / Data Transmission

Internet Security

This section is set up to cover the security aspects of using the Internet.  Its a big bad world out there full of big bad people... the internet allows these people to interacts with people that would have been previously out of their reach, thus exposing people to a lot of danger. What are the dangers?? how can you protect yourself??  If you cannot answer these questions (Even if you can)  continue to read through this section of the site...
  • Malware
  • Hackers
  • Anti - Virus Software
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Malicious Software


Often when things go wrong with somebody's computer they are quick to blame a "Virus". Now whilst it is possible that a virus may be causing the issue it is also very likely that viruses are taking the blame unnecessarily. Unless you know specifically that you have a virus it is safer to assume that you have malware.

Malware - The umbrella term referring to any Malicious software

There are many types of Malware all with different capabilities and characteristics.  We will be taking a closer look at Viruses, Worms, Trojans, Spyware, Adware and Ransom-ware.
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Viruses


Viruses are files that attach themselves to existing programs. They are only activated once the file that they have attached to is opened.

Once they have been activated a virus can perform any task that it has been programmed to do. This can include replicating themselves which makes it hard to get rid of them and hogs system resources (Memory and Processing).

Malicious harm that viruses can cause includes:
- Stealing of corrupting data
- Spamming contacts
- Consuming your bandwidth or hard disk

Not all viruses will cause harm to your system... some can just be annoying like the You are an idiot" Virus...


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Trojans


​A Trojan horse is software that will appear to have a legitimate purpose, however, it will actually perform another more malicious action.

Trojans are named after the Trojan Horse (Greek Mythology) where a giant wooden horse was given as a gift.. little did the recipients know that the "Gift" contained enemy solders.
 
The other task that a Trojan can perform ranges from the mildly annoying to the more serious just like viruses.
 
Trojans are well known for creating “backdoors” that give malicious users full access to the infected computer!
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Worms


Unlike Viruses, worms can act as a standalone file, this means that they do not have to rely on being attached to another file.

Worms are commonly know for self replicating, once activated they will continue to create copies of themselves.  This will cause the computers memory and processing resources to become overloaded.

What's worse is that worms also have the capability of replicating themselves across a network from one device to another causing a lot of disruption!
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Adware


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If you are being spammed by lots of adverts like the above image, it is likely that your computer is infected with adware.

Adware are responsibly for the annoying popups and adverts that will often appear (Quite irritatingly) on people computers.  Luckily they wont often do any other harm to your computer, instead they seek to draw you to certain websites and in return they will either steal / sell your data or get paid per click.

Spyware

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Spyware is a type of software that will secretly (hence the SPY part) gather information / data from your computer.

It is very dangerous as it can collect information such as:

Credit card Information
Passwords
Usernames
Email Addresses
Search history
Private conversations
This information can be gathered by monitoring your actions, but beware, spyware will also look at your cookies which may store personal information.

Once Spyware has gathered your information it will sent it back to the person that made the spyware.  This person will then attempt to sell the data for advertising or even use it to steal your identity.

Ransomware


Ransomware is software that will prevent the user from using their computer until a fee is paid.  It is essentially holding your computer hostage until you pay the ransom.

Often Ransomware will make blackmail style threats of releasing embarrassing material is money is not paid.

Hacking
Hacking is when a person gains access to a computer or data WITHOUT PERMISSION from the owner

Examples of hacking...
Guessing the password to your friends Facebook account
Picking up somebody's phone and looking at their pictures without their permission
Finding a way around the governments firewall and stealing their information on aliens!
Why do people hack?
People hack for a number of different reasons, some of these are...

  • Malicious intent - To cause somebody harm
  • Financial gain - To gain money
  • Fun - Some hackers enjoy the challenge
  • Notoriety / Reputation - Hackers like to show off to other hackers
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​Types of Hacker
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Not all hackers have the same motivation or reason for hacking. Generally there are three different types of hacker...
White Hat Hackers
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White hat hackers will usually be hired by companies to try and break their security system.  If the hacker finds a vulnerability and is able to hack them,  they will inform the company how and suggest how they could fix it.

White hat hackers have permission to hack and it is legal.
Grey Hat Hackers
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Grey hat hackers run a fine line between being legal and illegal.  A grey hat hacker will try to hack a company or person,  if they find a way to hack that company they will inform the company and ask for a fee to fix it... if they do not pay then the hacker may do something bad.

Grey hat hacking can sometimes seem like black mail and therefor has morality issues.
Black Hat Hackers
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A Black hat hacker hacks for personal and often malicious reasons.  They do not have permission to hack, nor do they wish to help their victims.
Black hat hackers may wish to hack for revenge, financial gain or even political reasons.

​Black hat hackers do not have permission and hack illegally.

Botnets
Bot nets are a scary thing that sounds like something from a sci fi movie!  A hacker gain massive amounts of processing power for their attacks by setting a bot net up

A botnet is essentially a large amount of computers that have been compromised by a hacker and as a result the have control of a large number of computers.  The hacker will gain access to these computers by infecting them with malware. Once they have control of these computers they can be used to:
  • Cause a DOS attack by all accessing a particular service and using the bandwidth
  • Commit click fraud - The hacker can direct all computers to click on adds and collect the revenue
  • Illegal material can be stored on bot net computers offering the hacker protection
  • Spam email can be sent from all bot net computers.
​Botnets were recently a part of the video game "Watch dogs 2" where a group of "Hacktivists" created a mobile app that would make peoples phone a part of their bot net.  They would then use the combined processing power of the phones to defeat the government system.
Anti - Virus Software
To protect yourself from hackers and malware it is important that you use anti virus software and keep it up to date.
Antivirus software is designed to protect your computer from all malware not just virus'
How does it work?
  • Anti virus software contains a dictionary full of code snippets  taken from known malware
  • Each time a new file enters a computer system, the anti virus software will examine the files code
  • The code form the new file is compared to the dictionary of known malware
  • If the code matches something in the dictionary, the anti virus will assume that it is malicious and take action to delete or quarantine the file.
  • If the code does not match the dictionary  the file will be allowed to enter the computer and run
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Warning - Keep it up to date!
It is very important that you keep your antivirus software up to date, around the world hackers create new malware every day.  If this new malware is not added to your antivirus dictionary, it will not be detected and will be allowed into your computer to do damage.

Each time you update the antivirus software it will update the dictionary with newer code snippets of new malware, therefor keeping you as safe as you can be.

Be warned though... you will never be 100% safe, if a hacker alters the code just enough that it does not match in the dictionary, the anti virus software will be unable to detect it.


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Est. 2015 - Copyright © 2020