Lesson 1: Advanced Threats and Attack Techniques

Modern cyber threats often target the confidentiality, integrity, and availability (CIA) of information systems. Malware is malicious software designed to disrupt or gain unauthorized access. Types of malware include viruses (self-replicating code attaching to files), worms (standalone programs that spread across networks), trojan horses (malicious code disguised as legitimate software), and ransomware (encrypts files to extort payment). Each can steal data, corrupt information, or block system availability. For example, ransomware like WannaCry can make critical data inaccessible until a payment is made. Organizations must use up-to-date antivirus software and backup systems to mitigate these threats.

Attackers often use social engineering to trick users into revealing credentials or downloading malware. Phishing is a common tactic: fraudulent emails or messages mimic trusted sources to steal passwords or install malware. Variations include spear-phishing (targeted emails) and vishing (phone-based phishing). For instance, a fake email claiming to be from "HR Department" asking to reset your password can compromise corporate systems. Vigilant practice—such as verifying the sender's address, not clicking unknown links, and never giving out passwords—helps prevent these attacks.

Many attacks exploit web applications. SQL Injection (SQLi) occurs when attackers insert malicious code into database queries, potentially exposing or altering data. Cross-Site Scripting (XSS) allows attackers to inject scripts into web pages that run in other users' browsers. Cross-Site Request Forgery (CSRF) tricks authenticated users into submitting unintended commands. These attacks exploit poor input validation or session management. For example, a vulnerable login form that concatenates input directly into a SQL query can allow an attacker to retrieve user passwords via SQLi.