100-160 Practice Test

The Cisco CCST Cybersecurity (100-160) is a foundational-level Cisco certification. The exam has 35 questions, runs 50 minutes, costs $125, and requires a passing score of ~70%. CertSharp provides 500 exam-style 100-160 practice questions — 30 free with no credit card — each with a detailed explanation.

1. Question 2Essential Security PrinciplesEasy

   An attacker floods a target service with traffic from thousands of compromised devices so that legitimate users cannot connect. Which attack does this describe?

   • A

     A man-in-the-middle attack that intercepts traffic between two parties

   • B

     A privilege escalation attack that raises an attacker level of access

   • C

     A SQL injection attack that manipulates a backend database query

   • D

     A distributed denial-of-service attack launched from many compromised hosts

   Show answer & explanation

   Correct answer: D — A distributed denial-of-service attack launched from many compromised hosts

   A distributed denial-of-service attack uses many compromised hosts, often a botnet, to overwhelm a target so legitimate users are denied service. A man-in-the-middle attack intercepts communications. Privilege escalation raises access rights, and SQL injection manipulates database queries.

2. Question 3Essential Security PrinciplesMedium

   A user reports that a free game they installed also installed hidden software that displays pop-up ads and tracks browsing. Which malware types are involved?

   • A

     A worm that self-replicated across the network without any file

   • B

     A rootkit that replaced core operating system kernel components

   • C

     A ransomware payload that encrypted the user personal documents

   • D

     A trojan that delivered bundled adware and tracking spyware

   Show answer & explanation

   Correct answer: D — A trojan that delivered bundled adware and tracking spyware

   A trojan disguises itself as desirable software, here a game, while delivering hidden adware and spyware that show ads and track activity. A worm self-replicates without a host program. A rootkit subverts the operating system core, and ransomware encrypts files for extortion - neither matches the described behavior.

3. Question 4Essential Security PrinciplesEasy

   An online store goes offline during a holiday sale because its servers are overwhelmed by traffic. Which element of the CIA triad is most directly affected?

   • A

     Confidentiality, because attackers can now read the stored customer data

   • B

     Integrity, because the product database records are being silently changed

   • C

     Availability, because legitimate users can no longer reach the service

   • D

     Authenticity, because the server can no longer prove its own identity

   Show answer & explanation

   Correct answer: C — Availability, because legitimate users can no longer reach the service

   Availability ensures systems and data are accessible to authorized users when needed; an overwhelmed server denies that access. Confidentiality concerns disclosure of data, which is not implied here. Integrity concerns unauthorized changes to data, also not implied. Authenticity concerns proving identity and is unrelated to the outage.

4. Question 5Essential Security PrinciplesMedium

   During a design review, an engineer proposes layering a firewall, network segmentation, endpoint protection, and user training. Which security principle does this approach illustrate?

   • A

     Least privilege, which grants users the minimum access they require

   • B

     Separation of duties, which splits a task across two or more people

   • C

     Security through obscurity, which relies on hiding implementation details

   • D

     Defense in depth, which uses multiple overlapping layers of controls

   Show answer & explanation

   Correct answer: D — Defense in depth, which uses multiple overlapping layers of controls

   Defense in depth places several independent layers of controls so that the failure of one layer does not expose the asset. Least privilege limits access rights. Separation of duties divides sensitive tasks among people. Security through obscurity relies on secrecy of design and is not a substitute for layered controls.

5. Question 6Essential Security PrinciplesEasy

   A hospital encrypts stored patient records so that only authorized clinicians can read them. Which element of the CIA triad does this control primarily protect?

   • A

     Confidentiality, ensuring information is disclosed only to authorized parties

   • B

     Integrity, ensuring information is not altered by an unauthorized party

   • C

     Availability, ensuring information is accessible whenever it is needed

   • D

     Accountability, ensuring actions can be traced to an authenticated user

   Show answer & explanation

   Correct answer: A — Confidentiality, ensuring information is disclosed only to authorized parties

   Encryption restricts readability to holders of the key, which protects confidentiality - the assurance that data is disclosed solely to authorized parties. Integrity concerns unauthorized modification rather than disclosure. Availability concerns timely access. Accountability links actions to identities and is not part of the classic CIA triad.

6. Question 7Essential Security PrinciplesMedium

   A trusted employee with valid access gradually copies confidential designs to sell to a competitor. Which threat category does this represent?

   • A

     An advanced persistent threat run by an external state-sponsored group

   • B

     An insider threat, originating from a person with legitimate access

   • C

     A supply-chain attack that compromises a third-party software vendor

   • D

     A zero-day attack that exploits a previously unknown software flaw

   Show answer & explanation

   Correct answer: B — An insider threat, originating from a person with legitimate access

   An insider threat comes from someone with legitimate access, such as an employee who misuses that access to steal data. An advanced persistent threat is a stealthy external campaign. A supply-chain attack targets third-party providers, and a zero-day exploits an unknown flaw.

7. Question 8Essential Security PrinciplesEasy

   An attacker follows an employee through a badge-controlled door without presenting credentials. Which social engineering technique is this?

   • A

     Phishing, where an attacker sends fraudulent messages to harvest data

   • B

     Tailgating, where an attacker physically follows an authorized person inside

   • C

     Vishing, where an attacker uses voice calls to manipulate a victim

   • D

     Smishing, where an attacker sends fraudulent text messages to a victim

   Show answer & explanation

   Correct answer: B — Tailgating, where an attacker physically follows an authorized person inside

   Tailgating is a physical social engineering technique in which an attacker follows an authorized person through a secured entrance. Phishing uses fraudulent email or messages. Vishing uses voice calls, and smishing uses fraudulent SMS text messages to deceive a target.

8. Question 9Essential Security PrinciplesMedium

   A security team agrees to obtain proper authorization, avoid harm, and respect privacy during testing. These commitments most directly reflect which concept?

   • A

     A professional code of ethics that guides responsible security conduct

   • B

     A service level agreement that defines ensured response times

   • C

     A disaster recovery plan that restores systems after a disruption

   • D

     A change management policy that controls modifications to systems

   Show answer & explanation

   Correct answer: A — A professional code of ethics that guides responsible security conduct

   A code of ethics defines the professional standards, such as obtaining authorization and avoiding harm, expected of security practitioners. A service level agreement defines service performance commitments. A disaster recovery plan restores operations, and change management governs system modifications.

9. Question 10Essential Security PrinciplesEasy

   A new server is being prepared for production. The team disables unused services, removes default accounts, and applies current patches. What is this process called?

   • A

     System hardening, which reduces the attack surface of a device

   • B

     Penetration testing, which actively probes a system for exploitable flaws

   • C

     Threat modeling, which maps how an attacker might target a system

   • D

     Incident containment, which limits the spread of an active compromise

   Show answer & explanation

   Correct answer: A — System hardening, which reduces the attack surface of a device

   Hardening reduces a system attack surface by removing unnecessary services, default credentials, and unpatched software. Penetration testing probes for weaknesses but does not remediate them. Threat modeling is a design-time analysis. Containment is a response activity after an incident has already begun.