Threats to computer systems and networks

What are the different forms of attack?

• Malware

• Social engineering, e.g. phishing, people as the ‘weak point’

• Brute-force attacks

• Denial of service attacks

• Data interception and theft

• The concept of SQL injection

What is malware?

software that has been created with malicious intent to harm a computer system

Issues caused by malware

• files being deleted, corrupted or encrypted

• internet connection becoming slow or unstable

• computer crashing or shutting down

Types of malware:

• viruses

• worms

• Trojan

• spyware

• ransomware

What is a virus and what issues does it cause?

Software that replicates itself/spreads on a user’s computer.

Issues caused:

• fills disk space

• deletes/corrupts data

• allows unauthorised access to computer

• prevents applications from running correctly

What is a worm?

Software that replicates across a network. Will spread to other drives and computers on the network.

Uses up all the bandwidth

How does a worm infect other computers?

• Worms can infect other computers from

  • Infected websites

  • Instant message services

  • Email

  • Network connection

What is Trojan and what issues does it cause?

Trojan is malware disguised as legitimate software. Once it is installed it acts like a virus.

Issues:

• deleting files

• allowing unauthorised access

What is spyware and what issues does it cause?

Spyware is software that allow a person to spy on the users’ activities. Embedded into other software such as games or programs that have been downloaded from illegitimate sources.

Issues:

• spyware can record screens and log keystrokes to gain access to passwords and more

What is ransomware and what issues does it cause?

Ransomware is a form of malware that corrupts, encrypts or locks access to data.

The user cannot access the data again without paying money to get it back/decrypted.

What is social engineering?

Using deception to manipulate users to gain personal data.