1.4.1 Threats to Computer Systems & Networks

• What is malware?

  Malicious software.
• Typical actions of malware include:

  • Deleting or modifying files
  • Scareware (using fear to get their way)
  • Locking files e.g ransomware which encrypts all files and demands a large sum of money for them to be decrypted
  • Spyware (secretly monitors users)
  • Altering permissions via rootkits
  • Opening backdoors (holes in security)
• Viruses copy themselves and attach to certain files. They are spread by copying infected files and activated by opening infected files.
• Worms self-replicate without help from a user so spread very quickly. They exploit weaknesses in network security.
• Trojans are malware disguised as software. Users install them without realising they are malware.
• What is social engineering?

  Manipulating people as the ‘weak point’ to gain unauthorised access to information or systems.
• What is phishing?

  When criminals send emails or texts pretending to be from businesses and add links to spoof versions of the businesses’ websites. Users will input personal data thinking it is real and have their information consequently stolen.
• What is one sign of phishing?

  Poor grammar/spelling.
• What is shouldering?

  Stealing information via looking over someone’s shoulder.
• What is a brute-force attack?

  A type of active attack used to gain information via cracking passwords through trial and error, usually with aid from automated software.
• What is one system that prevents brute-force attacks?

  Locking accounts after a number of failed password attempts.
• What is a denial-of-service attack?

  Flooding a network with lots of traffic to make it incredibly slow or inaccessible.
• What is a passive attack?

  Where someone monitors data travelling on a network and intercepts any sensitive information they find. These attacks are hard to detect.
• What is an active attack?

  An attack which usually involves malware.
• What is an insider attack?

  Exploitation of network access to steal information.
• What is SQL?

  Structured Query Language - used to access information in databases.
• What are SQL injections?

  Pieces of SQL typed into a website‘s input box to reveal sensitive information.