Palo Alto Networks Certified Network Security Administrator (PCNSA)Cybersecurity FundamentalsEasy

A cloud service provider is experiencing a massive influx of traffic from thousands of compromised IoT devices, all simultaneously attempting to access a specific web application, rendering it unavailable to legitimate users. This scenario is a classic example of which type of attack?

  1. ABrute-Force Attack
  2. BMan-in-the-Middle (MitM)
  3. CDistributed Denial of Service (DDoS)
  4. DPhishing
Show answer & explanation

Correct answer: C. Distributed Denial of Service (DDoS)

A Distributed Denial of Service (DDoS) attack involves multiple compromised systems (like IoT devices forming a botnet) flooding the target with traffic, making it unavailable to legitimate users. This perfectly matches the scenario described.

Why the other options are wrong

  • A. Brute-force attacks involve systematically trying many passwords or passphrases until the correct one is found, not flooding a service with general traffic.
  • B. Man-in-the-Middle attacks involve an attacker intercepting communication between two parties, not overwhelming a service with traffic.
  • D. Phishing is a social engineering technique to trick users into revealing sensitive information, not a direct attack on service availability.

Distributed Denial of Service (DDoS)

A malicious attempt to disrupt the normal traffic of a targeted server, service, or network by overwhelming the target or its surrounding infrastructure with a flood of Internet traffic from multiple compromised computer systems.

  • Uses multiple compromised systems (botnet).
  • Floods target with overwhelming traffic.
  • Renders service unavailable to legitimate users.
  • IoT devices are common components of botnets.

Memory trick: DoS attacks stop service: DDoS uses many sources, DoS uses one.

More Cybersecurity Fundamentals questions