1.4 Network Security (1.4.1 And 1.4.2)

Question 1

Forms of attack

Answer 1

• malware
• social engineering
• brute force attack
• denial of service attacks
• data interception and theft
• SQL injection

Question 2

Malware and types of it

Answer 2

• executable programs that run on a computer

- e.g. computer virus, worm, Trojan horse and ransomware

Question 3

Computer viruses and worms

Answer 3

• viruses infect computers, replicate their code in other programs, infect other computers, and harm the computer by deleting, corrupting or modifying files
• worms replicate themselves in order to spread to other computers, they slow down networks and computers

Question 4

Trojan horses

Answer 4

• they have a program, game or cracked file which is something the user wants
• they have negative program code which causes damage, takes control or provides access to the computer

Question 5

Ransomware

Answer 5

• software which holds a computer hostage by locking or encrypting access to it
• if the data is encrypted, it won’t be able to be recovered unless backups are available
• once a ransom is paid to the attacker, access is restored

Question 6

Social engineering

Answer 6

• ability to obtain confidential information by asking people for it
• e.g. shoulder surfing, phishing

Question 7

Shoulder surfing

Answer 7

• ability to get information or passwords by observing as someone types them in
• either by looking over someone’s shoulder or using a CCTV camera

Question 8

Phishing

Answer 8

• emails, texts or phone calls sent to users commonly pretending to be from a bank or website
• messages will try to get personal information like: usernames, passwords, credit card details

Question 9

Brute force attacks

Answer 9

• a hacker tries every combination of password until the correct one is found
• this is done using a computer program

Question 10

Denial of service attacks

Answer 10

• a hacker infects a computer so that it sends as many requests to the server as it can
• the server then can’t respond fast enough so it slows or goes offline

Question 11

Data interception and theft

Answer 11

• allows the attacker to intercept communications between the user and the server
• the attacker can then:
  
  • eavesdrop to find passwords and personal information
  • add different information to a web page or other communications such as email

Question 12

SQL Injection

Answer 12

• it’s a database of query language
• takes advantage of web input forms to access or destroy data
• SQL commands can be input into web forms instead of the expected ‘real’ data
• this can be interpreted by vulnerable web applications and end up causing damage or releasing personal information

Question 13

Methods to prevent vulnerabilities

Answer 13

• penetration testing
• anti-malware software
• firewalls
• user access levels
• passwords
• encryption
• physical security

Question 14

penetration testing

Answer 14

• deliberately trying to find holes in your own system

goal is to:

• identify the targets of potential attacks
• identify possible entry points

Question 15

anti-malware software

Answer 15

• detects malware such as viruses, worms, trojans and spyware
• when a virus or new malware is detected it is sent to the anti-virus company
• they verify it is malware then create a signature of the virus
• they then add it to their virus database and tell computers to run an update
• viruses can morph, makes it harder to create a signature
• anti-malware software must be running at all times and has to be up to date

Question 16

firewalls

Answer 16

• separates a trusted network from an untrusted network
• data is sent around a network in small packets
• incoming and outgoing packets are checked against specified rules
• firewalls can be run on dedicated hardware or as software
• they may be built into your hardware

Question 17

firewall features

Answer 17

• preventing attackers from gaining access to computers on a network
• can block certain malicious computers by filtering packets from a certain IP address
• prevents access to certain ports on the network

Question 18

user access levels

Answer 18

• access rights may be set on disks, folders and files

Question 19

password policy

Answer 19

• passwords are often checked as they are created to make sure that they conform to the parameters given in a required policy

Question 20

encryption

Answer 20

• way of securing data so that it cannot be read without the encryption key
• if a hacker obtains data, they won’t be able to easily read it
• devices and computers can also have their storage and hard disk data encrypted
• websites use HTTPS to encrypt the connection to the server
• files can be encrypted individually on a computer using a password

Question 21

physical security

Answer 21

• where hardware, software and networks are protected by physical methods
• methods include: CCTV, security guards, intruder alarms