GCSE
Computer Science
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Introduction to GCSE Computer Science -
1.1 Systems Architecture -
1.2 Memory and Storage -
1.3 Computer Networks, Connections and Protocols -
1.4 Network Security -
1.5 Systems Software -
1.6 Ethical, Legal, Cultural and Environmental Impacts of Digital Technology -
2.1 Algorithms -
2.2 Programming Fundamentals -
2.3 Producing Robust Programs -
2.4 Boolean Logic -
2.5 Programming Languages and Integrated Development Environments
1. Computer Systems
1.4.1 Threats To Computer Systems and Networks
In this lesson, we will explore various methods used by cybercriminals to compromise devices and systems. Understanding these threats and their principles is crucial to defending against them effectively.
Malware
Malware is malicious software designed to infiltrate, damage, or gain unauthorised access to computer systems. It includes viruses, worms, Trojans, ransomware, and spyware.
- How the attack is used: Malware is often delivered via infected email attachments, compromised websites, or software downloads. Once installed on a system, it can replicate itself, steal sensitive data, and cause system instability.
- Purpose of the attack: The purpose of malware attacks can vary widely, including financial gain through ransom demands, data theft for identity theft or espionage, or disruption of operations for political or personal motives.
Example
Imagine you download a "free video converter" from an unofficial website. After installing it, your computer starts behaving strangely—pop-ups appear, files are encrypted, and you’re asked to pay to unlock them. This is a classic example of malware containing both a Trojan and ransomware.
| Type | Explanation |
|---|---|
| Viruses | A virus is a kind of malicious software that attaches itself to legitimate programs or files, spreading when the infected file is opened or executed. They can corrupt, delete, or steal data, and may spread to other systems. |
| Worms | Worms are self-replicating malware that spread across networks without needing to attach to a host file. Worms can consume network resources, slow down systems, and cause widespread damage. |
| Trojans | Trojans are malicious software disguised as legitimate or useful programs, tricking users into installing it. Once installed, Trojans can give attackers control over the system, steal data, or install other malware. |
| Ransomware | Ransomware is malware that encrypts a user's data and demands payment (a ransom) to restore access. Ransomware can result in data loss and financial extortion, often with no guarantee of data recovery even if the ransom is paid. |
| Spyware | Spyware is software that secretly monitors and collects user activity and data without consent. It can capture sensitive information, such as passwords, credit card numbers, and personal details, leading to identity theft or fraud. |
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Create a free accountMalware
- Malware is software designed to infiltrate, damage, or gain unauthorised access to systems.
- Common types include viruses, worms, Trojans, ransomware, and spyware.
- Viruses: Attach to files or programs and spread when the host is activated.
- Worms: Self-replicating malware that spreads across networks without a host file.
- Trojans: Disguised as legitimate software to trick users into installing them.
- Ransomware: Encrypts data and demands payment to restore access.
- Spyware: Secretly monitors user activity to collect sensitive data.
Social Engineering
- Social engineering exploits human psychology to gain confidential information or access.
- Techniques include phishing, pretexting, baiting, and tailgating.
Brute-force Attacks
- Brute-force attacks try all possible password combinations until access is gained.
- They use automated tools to rapidly attempt login credentials.
Denial of Service (DoS) Attacks
- DoS attacks overwhelm a system with excessive traffic, making it unavailable to users.
- The goal is to disrupt services or distract from other attacks.
Data Interception and Theft
- Data interception involves capturing sensitive information in transit.
- Techniques include sniffing, man-in-the-middle attacks, and data breaches.
SQL Injection
- SQL injection exploits vulnerabilities in web applications by injecting malicious SQL.
- It can bypass authentication, access or change data, or delete entire databases.