Threats to Computer Systems

• Forms of Attack


  Malware

  social engineering (e.g. phishing)

  brute-force attacks

  Denial of Service Attacks

  Data Interception and theft

  SQL injection
• Malware


  Comes from the words Malicious Software
• Malware are executable programs that run on a computer
• Types of Malware


  Viruses

  Worms

  Trojans

  ransomware
• Viruses


  infect computers

  replicate their code in other programs

  infect other computers

  harm computer by deleting, corrupting or modifying files
• Worms


  replicates itself to spread to other computers

  may cause no damage to attacked computer

  slow down networks and computers
• Trojan 


  trojans have a program, game or cracked file which the user wants

  they contain negative program code which causes damage, takes control or provides access to the computer

  the virus is hidden in the code
• Ransomware


  holds computer hostage by locking or encrypting access to it

  if data is encrypted no even cyber security professional will be able to recover the data unless backups are available

  once a ransom is paid to the attacker access it restored
• Social engineering


  ability to obtain confidential information by asking people for it
• examples of Social Engineering


  Shoulder Surfing

  Phishing
• Shoulder Surfing


  ability to get information or passwords by observing as someone types them in

  e.g. by looking over someone's shoulder or using a CCTV camera
• Phishing


  emails/text are sent to users commonly pretending to be a company that they are not

  these message will try to get personal information such as usernames, passwords, credit card details or other personal information
• What to look for in Phishing Email

  Greeting - Phishers dont know your name and only your email address

  sender's address - often a variation on actual address

  forged link - link may look genuine but it may not link to website given - roll mouse over link to see actual link

  request for personal infomation - genuine organisation never ask

  sense of urgency - make it seem like something bad will happen if it isnt completed quickly

  poor spelling and grammer
• Denial of Service (DoS)


  hacker will use or infect a computer so that it sends many requests to the server as it can (flood)

  the server cant respond fast enough so slows down or goes offline
• Man in the middle Attack

  allows the attacker to intercept communications between the user and server

  attacker can then eavesdrop to find passwords and personal information and add different information to a web page or other communications such as email

  connecting to an unencrypted Wi-Fi makes it easy to perform Man in the middle attack
• Brute Force Attack


  a program will try every combination of a password until the correct password is found
• SQL injection


  data base language so data is then accessed

  SQL injection takes advantages of web input forms to access or destroy data

  SQL commands can be input into web forms instead of expected 'real' data

  which can be interpreted by vunerable web applications and end up causing damage or releasing personal infomation
• Man in Middle data interception

  on public network hacker will place themselves between computer and network and retrieve data