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GCSE Computer Science · Malicious software

Malware and attack methods

Compare malware types and describe common attack methods such as brute force and denial of service.

Cybersecurity45-60 minutesSelf-contained lesson

Lesson overview

Compare malware types and describe common attack methods such as brute force and denial of service.

Focus: Malware and attack methods.

What you will learn

  • Define the key GCSE Computer Science terms used in malware and attack methods.
  • Explain how virus works in a practical scenario.
  • Compare ransomware with an alternative or related method.
  • Apply malware and attack methods accurately in exam-style questions.

Before you start

  • Cybersecurity threats.
  • File and software basics.
  • Networks.

Malware scenarios

Use the infected attachment, encrypted files and overloaded website examples below to identify attack types.

Malware and attack methods infographic

GCSE Computer Science infographic comparing malware types and attack effects with labels for Virus | Worm | Trojan | Ransomware | Spyware.
Use this visual to organise the key ideas for malware and attack methods.Download visual

Explanation

Malware is software designed to harm, disrupt, spy on or gain unauthorised access to computer systems.

Viruses attach to files and spread when files are run, worms spread across networks, trojans disguise themselves as legitimate software, spyware gathers information and ransomware encrypts data for payment demands.

Not every attack is malware: brute-force attacks repeatedly try credentials, and denial-of-service attacks try to make a system unavailable.

Worked examples

Applying malware

A user installs a fake game update.

The program secretly records keystrokes.

Login details are sent to an attacker.

Answer: This is malware behaving like spyware, because it disguises itself and gathers user information.

Quick checks

1. What is ransomware?

  1. a. Malware that encrypts or locks data and demands payment
  2. b. A faster processor
  3. c. A type of monitor
Reveal answer

Answer: a. Correct. Ransomware blocks access to data or systems to pressure the victim.

Not quite. Focus on virus in the scenario.

2. Which idea is most closely linked to malware and attack methods?

  1. a. A monitor brightness setting
  2. b. Denial of service
  3. c. A random file extension
Reveal answer

Answer: b. Correct. Denial of service is part of this topic.

Not quite. Choose the option that belongs to the Computer Science concept.

Practice

1. What is a trojan?

Reveal answer

Answer: Malware disguised as legitimate software.

Marking: Credit disguise and malicious purpose.

2. How does a brute-force attack work?

Reveal answer

Answer: It repeatedly tries passwords or keys until one works.

Marking: Credit repeated guessing.

3. What is the aim of a denial-of-service attack?

Reveal answer

Answer: To make a service unavailable to legitimate users.

Marking: Credit availability disruption.

4. Name one defence against malware.

Reveal answer

Answer: Antivirus, updates, cautious downloads, backups or access controls.

Marking: Credit valid defence.

Exam practice ladder

  • Fluency: recall the key term and use it accurately.
  • Application: apply the idea to the scenario rather than giving a generic definition.
  • Algorithmic reasoning: show the steps, condition or variable change clearly.
  • Evaluation: explain why one method, structure or control is suitable.

Answers and marking guidance

Exact answers and marking guidance are hidden under each question. For this lesson, earn marks by naming the correct Computer Science idea, applying it to the scenario and showing the logic or value change clearly.

Common mistakes

  • Using malware and phishing as exact synonyms.
  • Saying ransomware always steals money directly from a bank.
  • Ignoring backups as a defence.
  • Confusing denial of service with data encryption.

Extension

Compare ransomware and denial of service using attack method, impact and one suitable defence.

Next lesson

Next, continue with Social engineering and phishing.

Exam-board guidance

Aplailasain is an independent learning resource and is not endorsed by any exam board.

AQA GCSE Computer Science

AQA GCSE Computer Science: this skill supports problem solving, clear algorithms and accurate programming explanations.

OCR GCSE Computer Science

OCR GCSE Computer Science: expect precise algorithm reasoning, trace work and careful use of programming vocabulary.

Pearson Edexcel GCSE Computer Science

Pearson Edexcel GCSE Computer Science: practise explaining the method as well as giving the final answer or code.

Eduqas GCSE Computer Science

Eduqas GCSE Computer Science: secure the transferable idea first, then check how your class applies it in tasks.

WJEC Wales

WJEC Wales: use accurate terminology and show enough working for the examiner to follow your logic.

CCEA

CCEA: connect the idea to your class route and use the same algorithm, programming or systems vocabulary your teacher uses.