# **Cyber-attacks** A cyber-attack is a malicious and deliberate attempt by an individual or organization to breach the information system of another individual or organization. The primary goal is often to compromise security, privacy, or system availability, often targeting the CIA Triad (Confidentiality, Integrity, and Availability). ## **Types of Cyber-attacks** ### **DDoS (Distributed Denial of Service) Attack** An attack designed to make a website or system unavailable to its intended users. It works by flooding the target system with an overwhelming amount of traffic from multiple, often infected, sources known as **botnets**. This overload causes the system to slow down or crash, directly attacking the "Availability" pillar of security. ### **Ransomware** A type of malicious software (malware) that encrypts a user's files, making them inaccessible. The attackers then demand a payment (ransom), usually in cryptocurrency, in exchange for the decryption key to restore access to the files. ### **Spyware** Malware that secretly installs itself on a device to gather information about a person or organization without their knowledge. It can monitor keystrokes (**keylogging**), capture screenshots, track online activities, and send this sensitive data to an attacker. ### **Viruses** Malicious programs that attach themselves to legitimate files or programs. When an infected file is executed, the virus replicates itself and spreads to other files and systems. They can corrupt data, disrupt system operations, or cause crashes. ### **Phishing** A **social engineering** attack where attackers deceive victims into revealing sensitive information. This is typically done through fraudulent emails, messages, or websites that impersonate a trustworthy entity (e.g., a bank or a well-known company). The goal is to steal credentials like passwords and credit card numbers. ### **Malware (Malicious Software)** A broad term for any software intentionally designed to cause damage to a computer, server, client, or computer network. This category includes viruses, spyware, ransomware, trojans, and other harmful software. ### **Other Common Attacks** * **Man-in-the-Middle (MitM):** An attack where the attacker secretly relays and possibly alters the communications between two parties who believe they are directly communicating with each other. * **SQL Injection (SQLi):** An attack that involves inserting malicious SQL code into a web form or input field to manipulate a backend database and gain unauthorized access to data. ## **Comparison of Cyber-attacks** | Attack Type | Primary Goal | Method | | :--- | :--- | :--- | | **DDoS** | Disrupt service availability | Overwhelm a system with traffic from many sources. | | **Ransomware** | Financial extortion | Encrypt files and demand a ransom for the decryption key. | | **Spyware** | Information theft | Secretly monitor and collect data from a user's device. | | **Virus** | Damage & Replication | Attach to files, replicate, and spread to other systems. | | **Phishing** | Steal credentials | Deceive users into voluntarily providing sensitive information. | ## **Possible Questions/Answers** - **Q:** What is the main difference between a virus and spyware? **A:** A *virus* is designed to replicate and spread, often causing damage to files and systems. *Spyware* is designed to secretly collect and transmit a user's private information without their knowledge. - **Q:** How does a DDoS attack make a website unavailable? **A:** It floods the website's server with so much traffic from a distributed network of computers that the server cannot handle legitimate requests, causing it to slow down or crash. - **Q:** What is the goal of a phishing attack? **A:** To trick individuals into giving away sensitive information, such as passwords, credit card numbers, or other personal details, by pretending to be a trustworthy source.