A free, self-paced textbook in 8 chapters. Read a chapter, then drill it with the 256 companion flashcards using spaced repetition.
Cybersecurity is the practice of protecting systems, networks, devices, and data from unauthorized access, attack, or disruption. At the heart of the discipline lies the CIA triad:...
Controlling who can do what rests on the AAA framework: authentication, authorization, and accounting. Authentication verifies a user's identity, typically with credentials, tokens...
Cryptography is the mathematical backbone of confidentiality, integrity, and authentication. Symmetric encryption uses a single shared key for both encryption and decryption, makin...
Network defenses begin with the firewall, a device or software that filters traffic based on rules covering source, destination, port, and protocol. A stateless firewall inspects e...
Most modern attacks target applications, making secure software development a frontline concern. The OWASP Top 10 is a periodically updated list of the most critical web applicatio...
Attackers rely on a wide arsenal of techniques, often chaining multiple weaknesses together. Phishing tricks users into revealing credentials or executing malicious actions through...
Defenders think in terms of controls and their timing. Preventive controls stop incidents before they happen, detective controls find them when they occur, and corrective controls...
Frameworks and standards give organizations a shared vocabulary and a roadmap for managing risk. The NIST Cybersecurity Framework (NIST CSF) is a voluntary framework with five core...