What is a Denial-of-Service (DoS) attack?

What is a Denial-of-Service (DoS) attack?

• A. Attacks Aimed at Rendering a Network, System, or Service Unavailable by Overwhelming It with a Flood of Illegitimate Requests or Excessive Traffic.
• B. Data Exfiltration
• C. Social Engineering
• D. Buffer Overflow

Answer: (A)

The concept being tested is availability. A Denial-of-Service attack is designed to render a network, system, or service unavailable by flooding it with illegitimate requests or excessive traffic. This forces the target to spend its limited resources—such as bandwidth, CPU time, memory, or connection state—on handling the surge, leaving legitimate users unable to access the service or experience severe slowdowns. DoS attacks can come from a single source or multiple sources (the latter called a distributed DoS) to amplify impact. Other behaviors described correspond to different goals. Data exfiltration means stealing data from a system, social engineering tricks people into revealing information or performing actions, and a buffer overflow is a vulnerability exploit that can crash a program or take control of a system but isn’t, by itself, a definition of a Denial-of-Service attack.

The concept being tested is availability. A Denial-of-Service attack is designed to render a network, system, or service unavailable by flooding it with illegitimate requests or excessive traffic. This forces the target to spend its limited resources—such as bandwidth, CPU time, memory, or connection state—on handling the surge, leaving legitimate users unable to access the service or experience severe slowdowns. DoS attacks can come from a single source or multiple sources (the latter called a distributed DoS) to amplify impact.

Other behaviors described correspond to different goals. Data exfiltration means stealing data from a system, social engineering tricks people into revealing information or performing actions, and a buffer overflow is a vulnerability exploit that can crash a program or take control of a system but isn’t, by itself, a definition of a Denial-of-Service attack.