1.4.1 Threats to Computer Systems and Networks Flashcards
What is Malware?
Stands for “Malicious Software”
Created by a human to cause damage to a computer’s software including programs and files. Also used for unauthorised access by a hacker.
What are some examples of Malware?
- Virus
- Worm
- Trojan horse
- Ransomware
- Spyware
What is a Virus?
- Attached to a file/email and sent to target computer.
- It can replicate itself and spread system to system by attaching itself to other files.
- Virus only starts when activated by a human.
- Once active it can cause damage to computer software or files.
What is an example of a famous Virus?
A famous example is Storm Bot(2006) using enticing headlines to persuade people to click a link.
What is a worm?
- Replicates itself and spreads from system to system by finding weaknesses in software and networks
- A worm doesn’t need to attach itself to files or be activated by a human.
- They spread very quickly across a network once it has infiltrated
What is an example of a famous Worm?
A famous example is Nimda (2001) spreading across various weakness, it spread very quickly.
What is a Trojan Horse?
- Looks like legitimate software so people are tricked into downloading it
- Can give a hacker backdoor access to the system
- Does not replicate itself or infect other files.
What is an example of a famous Trojan Horse?
A famous example is Zeus (2007), used to steal banking information and more.
What is Spyware?
Secretly records the activities of the user and all information is passed back to hacker
What is Keylogger
Secretly records the key presses of a user and all information is passed back to hacker
What is Ransomware?
Locks files on a computer using encryption then demands money from victim to decrypt files, usually bitcoin as it is hard to trace
What is an SQL Injection?
- A SQL injection is where a malicious SQL command is entered into a data input box on a website
- If the website is insecure then the SQL command can trick the website into giving unauthorised access to the database.
What is a DoS?
- A denial of service attack is used to cause a website or server to overload and crash.
- This happens by flooding the website or server with rapidly repeating requests.
- This causes the website/server to overload, slow down and potentially be taken offline.
What is a DDoS?
- A distributed denial of service attack uses a botnet of infected systems to overload a server/website.
- A botnet is a large group of devices controlled by the hacker.
What is a Brute Force Attack?
- A hacker will use a computer program to test every possible combination of a password in order from start to finish.
- This method can be sped up by using multiple computers at the same time.
- Eventually the hacker will break in and gain unauthorised access.
What is Social Engineering?
- Used to trick users into breaking normal security systems and relies on human interaction.
- Humans are the weakest link in a system.
What are some examples of Social Engineering?
- Phishing
- Blagging
- Data interception
What is Phishing?
- Designed to gain sensitive information such as usernames, passwords and card details
- Most common form is emails.
- Just like fishing in real life “bait” is used to entice victims.
What are some examples to look out for in a phishing email?
- Informal greeting - they should know your name
- Grammar errors and misspelled words
- Email addresses and domain names don’t’ match
- Unusual content or request (usually money or login credentials)
- A sense of urgency
What is Blagging?
- Act of knowingly disclosing personal data or information without the consent of the owner of the data
- To prevent blagging the company needs to provide security training so employees don’t fall for this trick.
What is Human Error?
- Weak passwords/using the same password for all accounts
- Not keeping private information locked away
- Losing/stolen personal devices and - USB drives that contain private information
- Unknowingly downloading malware or falling for a phishing scam
What is Data Interception?
As data travels to its destination it can be intercepted through various means:
- Physically eg
- Stealing hard drives and other external hardware
- Connecting a wire to an established network
- Through wireless networks
- If data is not encrypted, it can be read
