1.3.3.9/10 Network Security

Question 1

What are the aims of network security?

Answer 1

Only allow authorised users to access what they need.

Prevent unauthorised access.

Minimise the potential damage caused by unauthorised access.

Question 2

What are the 3 types of hackers?

Answer 2

• Black-hat hackers
• Grey-hat hackers
• White-hat hackers

Question 3

What does a black-hat hacker do?

Answer 3

They attempt to gain access via nefarious means, typically to steal company secrets or cause damage.

Question 4

What does a grey-hat hacker do?

Answer 4

They are not employed by a company, but they still attempt to locate flaws in company-wide computer systems as a hobby. What they do is technically illegal, but they then inform the company of the flaw so the company can fix it.

Question 5

What does a white-hat hacker do?

Answer 5

These are security experts (often ex-hackers) employed by a company. Also known as ethical hackers, they use their expertise to try and find vulnerabilities and fix them.

Question 6

What does the term “malware” mean?

Answer 6

An umbrella term that covers any computer code written with the intent to frustrate or harm.

Question 7

What are the common types of malware?

Answer 7

Virus

Spyware

Denial-of-Service attack

SQL injection

Social engineering

Phishing (Social engineering)

Pharming (Social engineering)

Question 8

What is a virus?

Answer 8

A piece of code capable of copying itself and spreading throughout a system. They are typically designed to have a detrimental effect like corrupting a file system or destroying data.

Question 9

What is spyware?

Answer 9

A form of malware that covertly obtains information about a user’s computer activities by transmitting data from their device.

It can be used in a variety of ways to harvest all sorts of sensitive and personal data from a device

Question 10

What are the different ways in which spyware is used?

Answer 10

Internet surfing habits

Email addresses

Visited web pages

Downloads/download habits

Passwords

Credit card numbers

Keystrokes

Cookies

Question 11

What is a Denial-of-service (Dos) attack?

Answer 11

The attacker floods a server with useless traffic, causing the server to become overloaded.

Many of the past Dos attacks take advantage of the limitations of the TCP/IP stack.

They often target web servers of high-profile organisations such as banks, large scale e-commerce businesses and governments.

They typically cost a great deal of time and money to handle.

Question 12

What is a Distributed Denial-of-service (DDos) attack?

Answer 12

Multiple systems orchestrate a synchronised attack on a single computer system.

These multiple systems are in different locations and in some instances, the owners of these systems are unaware they’re being used. This leaves them with the classification of zombie.

Question 13

What is SQL injection?

Answer 13

A code injection technique used to attack data-driven applications. This attack is used to breach poorly coded database applications. Code is entered into input text boxes that are executed by the server.

Question 14

What does Social Engineering mean?

Answer 14

An umbrella term describing the various types of malware that prey upon human error with the intention of obtaining private information or access to a system.

Social engineering scams lure users into exposing data, spreading data or providing access to a system.

Question 15

What are some examples of social engineering scams used?

Answer 15

Baiting

Scareware

Pretexting/blagging

Phishing

Pharming

Shoulder-surfing

Quid pro quo

Vishing

Question 16

What is phishing?

Answer 16

An online fraud technique used by cybercriminals to trick users into giving out personal information such as usernames, passwords and credit card details.

Perpetrators disguise themselves as a trustworthy source in an electronic communication such as email or a fake website.

Question 17

What is pharming?

Answer 17

The use of malicious code installed onto a PC or a server that misdirect users to fraudulent sites without their knowledge.

Question 18

What are some ways cyber threats can be prevented and minimalised?

Answer 18

Firewalls

Secure passwords

Anti-virus/Anti-spyware software

Proxies

Encryption

Question 19

What is a firewall? What does it do?

Answer 19

A piece of software or hardware that is configured to let only certain types of traffic through it. Setting up a firewall can prevent:
- Unauthorised internet traffic outside a LAN
- Users in a LAN from accessing parts of the internet prohibited by the company they work for.

Firewalls can block certain ports and types of traffic. It can also inspect data travelling across it to see if it looks suspicious.

Operating systems and routers come with built in firewalls. More sophisticated firewalls can be purchased separately.

Question 20

What is Anti-virus/spyware software?

Answer 20

These applications come pre-installed with your operating systems, though you can purchase and install others from dedicated companies.

Detects and deletes these strains of malware from a system.

Question 21

Why is keeping software up to date necessary?

Answer 21

It is crucial to always add the latest patches to a system as early builds are often exploited by more bugs and malware.

Question 22

What is a proxy?

Answer 22

A physical device placed between a network and a remote source. All traffic travels through the device on its way in and out of a network.

Proxies ensure there is no direct, physical connection between a user and a remote source.

Proxies hold some cache so users can access their regularly visited websites without needing the internet.

Proxies do not encrypt data, making them less secure than Virtual Private Networks (VPN)

Proxies allow for anonymous internet usage.

Question 23

How can a proxy be used for web requests?

Answer 23

If the web page is not on the proxy’s ban list, it will be moved onto the request list. It can also look at the page itself and determine whether it should pass this to the user or not.

Question 24

How are humans susceptible to cyber-threats? (How are people the weak point?)

Answer 24

Sharing passwords

Losing memory sticks/laptops

Writing passwords down near the computer

Leaving printouts on desks

Not logging off/locking computers

Not installing operating system updates

Not keeping anti-malware up to date.

Not encrypting data

Not applying security to wireless networks