A cybersecurity threat is a potential malicious action that can compromise data or system security through attacks on confidentiality, integrity, or availability. These threats come from diverse sources—cybercriminals, hackers, insiders, and nation-state actors. Their motives range from financial gain and espionage to activism and system disruption.

These threats fall into several distinct categories, each with its own attack methods. Here are the most common types:

Malware

Phishing Attacks

Denial of Service (DoS) and Distributed Denial of Service (DDoS)

SQL Injection (SQLi)

Man-in-the-Middle (MitM) Attacks

Cross-Site Scripting (XSS)

Credential Stuffing

Insider Threats

Social Engineering Attacks

Advanced Persistent Threats (APTs)

• **Malware:** Malware (short for malicious software) is one of the most common and widely recognized forms of cyberattack. It refers to any software intentionally designed to cause harm to a system or network.

  Types of Malware:

  • Viruses: Programs that attach themselves to legitimate files or programs and spread when the infected program is executed. They can corrupt or delete files.
  • Worms: Similar to viruses, but unlike viruses, worms are self-replicating and can spread across networks without human intervention.
  • Trojans: Malicious software disguised as legitimate software. Once installed, they can steal data, provide remote access, or cause other harm.
  • Ransomware: A form of malware that locks or encrypts the victim's data and demands a ransom in exchange for unlocking or decrypting it (e.g., WannaCry, CryptoLocker).
  • Spyware/Adware: Malware designed to gather information (keylogging, screen scraping, etc.) without the user's knowledge or consent.

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• **Phishing Attacks:** Phishing is a social engineering attack where attackers attempt to trick individuals into providing sensitive information, such as usernames, passwords, credit card numbers, or other personal details.

  Types of Phishing:

  • Email Phishing: Attackers send fraudulent emails that appear to come from trusted sources (e.g., banks, companies). These emails typically include links to fake websites or attachments designed to steal data.
  • Spear Phishing: A more targeted form of phishing, where attackers personalize the message to a specific individual or organization, often using information obtained from social media or other sources.
  • Vishing (Voice Phishing): Attackers use phone calls or voice messages to trick victims into giving up sensitive information (e.g., pretending to be from a bank).
  • Smishing (SMS Phishing): Similar to vishing, but conducted via text messages, often with links to malicious websites or fake login pages.

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• **Denial of Service (DoS) and Distributed Denial of Service (DDoS):** Denial of Service (DoS) attacks aim to make a system or network unavailable to its intended users by overwhelming it with traffic or requests.

  Types:

  • DoS Attack: A single source floods a network, server, or website with traffic, rendering it unable to respond to legitimate requests.
  • DDoS Attack: A more powerful version of DoS, where the attack comes from multiple systems or a botnet. This makes it harder to mitigate because the attack traffic comes from many sources.

  Common DDoS Techniques:

  • UDP Flood: Sending large numbers of User Datagram Protocol (UDP) packets to random ports on the target system, causing it to overload.
  • SYN Flood: Sending a large number of "SYN" requests (part of the TCP handshake) to a target, which exhausts resources and causes the server to become unresponsive.