Certified: The GIAC GISF Audio Course

In this episode, we’re going to build a plain-language glossary, but we’ll do it in a way that works for audio and for real recall under pressure. When beginners study cybersecurity, it is easy to drown in vocabulary and still feel unsure what the words mean in a practical sense. The goal is not to sound technical. The goal is to hear a term and instantly understand what problem it describes, why it matters, and what kind of action it points toward. That kind of instant understanding is what helps on the exam, and it also helps you keep your thinking organized when a scenario feels messy. As we move through core terms, notice that many of them come in pairs or sets that explain each other. When you can connect the terms into a mental model, you stop memorizing and start recognizing.

Before we continue, a quick note: this audio course is a companion to our course companion books. The first book is about the exam and provides detailed information on how to pass it best. The second book is a Kindle-only eBook that contains 1,000 flashcards that can be used on your mobile device or Kindle. Check them both out at Cyber Author dot me, in the Bare Metal Study Guides Series.

A good place to start is with the three outcomes security is trying to protect: Confidentiality, Integrity, and Availability (C I A). Confidentiality means information is only seen by people who are allowed to see it, so a leak or unauthorized access is a confidentiality failure. Integrity means information stays accurate and unaltered, so tampering, unauthorized changes, and manipulated records are integrity failures. Availability means systems and data are accessible when needed, so outages, denial of service, and destructive attacks are availability failures. Under pressure, the trick is to map a scenario to one or more of these outcomes quickly. If a question describes stolen customer records, think confidentiality first. If it describes altered transaction logs, think integrity. If it describes a service that cannot be reached, think availability. Many real incidents affect more than one part of C I A, but starting here keeps you grounded.

Now connect those outcomes to risk language, because exam scenarios often use these words as if you already know them. A threat is a potential cause of harm, like a criminal group, a malicious insider, or even a natural disaster. A vulnerability is a weakness that could be exploited, like an unpatched system, a misconfiguration, or a poorly designed login process. A risk is the chance that a threat will successfully use a vulnerability to cause impact, and impact is the harm that would result, such as financial loss, downtime, or loss of trust. A common beginner mistake is treating threats and vulnerabilities as the same thing. The threat is the actor or event that could cause harm, and the vulnerability is the weakness that makes harm possible. When you hear the word control, think of it as a safeguard that reduces risk by lowering likelihood, lowering impact, or both.

Controls come in a few useful categories that make recall easier. Preventive controls try to stop bad outcomes before they happen, like strong authentication and secure configuration. Detective controls help you notice that something suspicious is happening, like monitoring logs and alerting. Corrective controls help you recover after something goes wrong, like backups and restoration procedures. Another helpful pair is technical controls versus administrative controls. Technical controls are enforced by technology, like access rules and encryption, while administrative controls are enforced by people and process, like policies, training, and approval workflows. Under pressure, you can simplify this by asking one question: is the control trying to stop, detect, or recover. If the scenario is about preventing unauthorized access, you expect preventive controls. If it is about spotting an intrusion quickly, you expect detective controls. If it is about restoring services after damage, you expect corrective controls.

Identity language is another area where beginners can get tangled, so keep it clean. Authentication is proving who you are, like presenting evidence that you are the account owner. Authorization is what you are allowed to do after you are authenticated. The exam often tests this distinction because many breaches happen when authorization is weak, not when authentication is bypassed. Least privilege means giving an account only the permissions it needs and nothing more, which reduces blast radius when an account is compromised. Privileged access refers to high-power permissions, like administrator capabilities, and those privileges deserve extra protection because they can change security settings and access sensitive systems. You will also hear Identity and Access Management (I A M), which is the overall practice of creating identities, assigning permissions, and controlling access over time, including onboarding and offboarding. When you are unsure, anchor to the sequence: authenticate first, authorize second, and keep privileges as small as possible.

A closely related term is Multi-Factor Authentication (M F A). The simplest way to define M F A is that it requires more than one independent proof of identity, so stealing one proof is not enough. This is powerful, but the important exam mindset is that M F A reduces risk, it does not erase it. Attackers may steal session tokens, trick users into approving prompts, or find paths where M F A is not enforced. That is why you also care about session management, which is how a web or cloud service keeps you logged in safely after the initial login. If a session token is stolen, an attacker may not need your password. Another useful term here is conditional access, which means access decisions depend on context like device health, location, and risk signals. Even as a beginner, you can remember a simple rule: stronger identity controls matter most where privileges are high and data is sensitive.

Now let’s build a plain-language foundation for web security terms, because they show up constantly. Input validation is the practice of treating all user input as untrusted and ensuring it matches what the system expects before using it. Injection is a broad idea where attackers manipulate input so the application does something unintended, often by altering how a backend system interprets a request. Broken access control means the application fails to enforce permissions on every request, so users can reach data or functions they should not. Cross-Site Scripting (X S S) is when untrusted input ends up running as script in another user’s browser, often leading to stolen session data or unwanted actions. Cross-Site Request Forgery (C S R F) is when a user’s browser is tricked into sending an unwanted request to a site where the user is already logged in. If you remember nothing else, remember that many web risks are about trusting input too much or trusting sessions too blindly.

When we shift from vocabulary to attacker behavior, it helps to use the idea of an attack lifecycle. Initial access is how the attacker gets in, such as phishing, credential theft, or exploitation. Post-exploitation is what happens after entry, when attackers try to expand their power and reach. Privilege escalation is gaining higher permissions than you started with. Credential theft is stealing passwords, tokens, or keys so the attacker can impersonate users or services. Lateral movement is moving from one system to another inside the environment, usually to reach more valuable targets. Internal discovery is the attacker mapping the environment, learning where important systems and data live. These terms matter because they help you anticipate next moves. If you see evidence of a foothold, you immediately ask whether the attacker is likely trying to steal credentials, escalate privileges, or move laterally.

You also need a clean mental model of stealth and persistence terms. Persistence means the attacker establishes a way to come back even after a reboot or cleanup attempt, which turns a one-time incident into an ongoing problem. Living off the land is when attackers use legitimate tools and normal features already present in the environment so their activity blends into routine operations. Command and Control (C 2) is the communication channel attackers use to maintain remote control of compromised systems, issue instructions, and receive results. These three ideas often appear together in real intrusions. If an attacker is living off the land, you might not see obvious malware files. If they have C 2, they may be actively controlling systems over time. If they have persistence, removing one artifact may not remove the threat. Under pressure, remember the story: persistence is staying power, living off the land is blending in, and C 2 is remote control.

Data protection terms are another high-yield cluster, especially in cloud and SaaS environments. Data at rest means stored data, like files in storage or records in a database. Data in transit means data moving between systems, like across a network connection. Encryption is a method of protecting data by making it unreadable without the correct key, but keys are as important as encryption itself because whoever controls the keys can often access the data. Data exfiltration means data is moved out of the environment without permission, often after staging, which is collecting and packaging data internally before moving it out. Data Loss Prevention (D L P) refers to controls designed to prevent or detect unauthorized movement of sensitive data, such as blocking risky sharing or alerting on unusual exports. The beginner-friendly way to remember this is that data security is about controlling access, controlling sharing, and being able to detect abnormal movement patterns.

Now tie the vocabulary back to defensive visibility, because terms are easier to remember when they have a job. Logs are recorded events, like sign-in attempts or configuration changes. Telemetry is a broader stream of signals about system behavior, which can include logs but also includes measurements and richer behavioral data. An alert is a decision that some pattern deserves attention, not just a loud log entry. Correlation is connecting separate events into a meaningful story, because isolated events can be misleading. Security Information and Event Management (SIM) refers to centralizing and correlating events so investigations are faster and patterns are easier to see. Endpoint Detection and Response (E D R) focuses on what happens on devices, like processes and file activity, while Network Detection and Response (N D R) focuses on communication patterns and data flows. Under pressure, remember the viewpoint rule: endpoints tell you what ran, networks tell you what talked, and correlation tells you what it means together.

Incident response vocabulary is also essential, because exams often test how you think when something goes wrong. Triage means quickly assessing an alert to decide severity and next actions. Containment means limiting damage by stopping spread and cutting off attacker access. Eradication means removing the attacker’s presence, such as persistence and malicious artifacts, so the threat is actually gone. Recovery means restoring normal operations safely and verifying systems are stable and trustworthy. Lessons learned means reviewing what happened and improving controls so the same path is harder next time. Another important pair is severity and confidence. Severity is the potential impact if the alert is real, and confidence is how likely it is that the alert truly indicates malicious activity. If severity is high, you may act faster even with moderate confidence, but you still verify as you go.

Now let’s connect terms about people and process, because many security failures are role failures. Shared responsibility means security outcomes depend on multiple parties, such as cloud providers, internal teams, and end users, each owning different layers. Accountability means someone is clearly responsible for an outcome, not just for doing a task. Separation of duties means no single person should control every step of a high-impact process, which reduces fraud and error. Security awareness is not memorizing rules, it is building habits that prevent common mistakes and speed reporting when something seems off. A key term here is social engineering, which is manipulating human trust to bypass technical controls, often using urgency, authority, or fear. When you see a scenario involving a suspicious request for credentials or money, the right response often involves independent verification and a process guardrail, not just a technical control.

To make this glossary usable under pressure, focus on recognition triggers rather than perfect wording. If you hear public data exposure, think confidentiality and access control. If you hear altered records, think integrity and authorization checks. If you hear service outage, think availability and recovery planning. If you hear suspicious login patterns, think authentication, M F A, and session risk. If you hear abnormal internal access chains, think credential theft, privilege escalation, and lateral movement. If you hear regular outbound connections, think C 2 and investigate the relationship between endpoint behavior and network patterns. If you hear large data movement, think staging and exfiltration, then ask whether D L P controls and logging would reveal it. These associations are what turn vocabulary into a practical map.

By the end of this lesson, the main goal is that essential terms stop feeling like disconnected definitions and start feeling like mental handles you can grab quickly. C I A keeps you focused on outcomes, risk language helps you reason about likelihood and impact, identity terms clarify who can do what, web terms explain how input and sessions can be abused, post-exploitation terms describe how attackers expand control, and defensive visibility terms explain how you catch the story across logs, telemetry, and alerts. People-and-process terms remind you that responsibility and habits matter as much as technology. The decision rule to remember is this: when you meet an unfamiliar scenario, translate it into these core terms first, because once you can name the type of risk, the likely attacker goal, and the control category, the right answer becomes much easier to see.