Identifying & Preventing Threats to Computer Systems & Networks Flashcards

All 18 cards in this deck

What is malware?

Software written to damage, disrupt or gain unauthorised access to a computer system.
e.g. viruses, worms, trojans, ransomware, spyware

What does ransomware do to a system?

Encrypts the user's files so they cannot be opened, then demands a payment for the decryption key.

An employee receives an email that looks like it is from their bank, asking them to click a link and enter their login details. What form of attack is this?

Phishing — a form of social engineering. Its purpose is to steal personal data such as usernames, passwords or bank details.

True or false? The people who use a system are often its weakest point in terms of security.

True. Attackers use social engineering to trick users into revealing passwords or access, bypassing technical security.

What is a brute-force attack?

An attack that automatically tries many possible combinations of characters to guess a password, in order to gain unauthorised access to an account or system.

What is a denial of service (DoS) attack?

Flooding a server with so many requests that it cannot respond to genuine users, making the service slow or completely unavailable.

What is data interception and theft?

Capturing data as it travels across a network (e.g. packet sniffing) and stealing it, leading to stolen passwords, fraud or loss of confidential data.

What is SQL injection?

Typing SQL code into a website input box so that it is run by the database, letting an attacker view, change or delete data such as usernames and passwords.

What is penetration testing?

Deliberately attacking a system to find its weaknesses before a real attacker does; the vulnerabilities found are reported so they can be fixed.

What does anti-malware software do?

Scans files and incoming data and compares them with known malware signatures, then quarantines or deletes anything it finds and stops it running.

What is a firewall?

Software or hardware that stops unauthorised access to a network by checking incoming and outgoing traffic against a set of rules and blocking anything not allowed.

How do user access levels limit the damage caused by an attack?

Each user can only reach the files and functions their role needs, so a compromised account gives the attacker access to only a small part of the system.

What makes a strong password policy?

Long passwords mixing upper and lower case letters, numbers and symbols, changed regularly, not reused, with a limit on failed login attempts.

How does encryption protect data?

It scrambles the data into ciphertext using a key, so anyone who intercepts or steals it cannot understand it without the key.

True or false? Encryption prevents data from being intercepted.

False. It does not stop interception — it makes the intercepted data meaningless without the decryption key.

Give three physical security measures used to protect a computer system.

Locked doors on server rooms, CCTV, security guards, biometric locks. They prevent theft of, damage to, or direct access to devices.

True or false? A firewall will stop an employee being tricked by a phishing email.

False. A firewall only filters network traffic; staff training and awareness are needed against social engineering.

What is the main reason an organisation should use several prevention methods together rather than just one?

No single method prevents every form of attack, so the layers cover each other's weaknesses.
e.g. a firewall cannot stop a user revealing their password to a phishing email