This CEH practice question tests your understanding of malware, social engineering and network attacks. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A network switch starts behaving like a hub, broadcasting all traffic to all ports. The security team suspects an attack that floods the switch with fake MAC addresses. Which attack is this?
MAC flooding
MAC flooding fills the CAM table with fake MACs.
ARP poisoning
Why wrong: ARP poisoning targets the ARP cache.
STP attack
Why wrong: STP attacks manipulate spanning tree protocol.
DNS spoofing
Why wrong: DNS spoofing corrupts DNS.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
MAC flooding
MAC flooding exploits the limited size of a switch's Content Addressable Memory (CAM) table. By sending thousands of packets with unique, fake source MAC addresses, the attacker fills the CAM table, forcing the switch to fail open and broadcast all incoming frames to every port, effectively behaving like a hub. This allows the attacker to capture traffic not originally destined for their port.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
MAC flooding
Why this is correct
MAC flooding fills the CAM table with fake MACs.
Related concept
Read the scenario before looking for a memorised answer.
ARP poisoning
Why it's wrong here
ARP poisoning targets the ARP cache.
STP attack
Why it's wrong here
STP attacks manipulate spanning tree protocol.
DNS spoofing
Why it's wrong here
DNS spoofing corrupts DNS.
Common exam traps
EC-Council often tests the distinction between MAC flooding (layer 2 CAM table exhaustion) and ARP poisoning (layer 2/3 cache manipulation), so candidates mistakenly choose ARP poisoning because both involve MAC addresses, but only MAC flooding causes the switch to broadcast traffic like a hub.
Detailed technical explanation
Under the hood, a switch's CAM table maps MAC addresses to specific port numbers and has a fixed size (e.g., 8,192 entries on older Cisco Catalyst switches). When the table is full, the switch enters a fail-open state, flooding frames out all ports in the same VLAN. In a real-world scenario, an attacker can use tools like macof (part of the dsniff suite) to generate 8,000+ random MAC addresses per minute, overwhelming the CAM table within seconds and enabling traffic sniffing on a switched network.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
A network engineer segments a warehouse floor into three subnets: 20 scanners, 5 printers, and 2 management hosts. Picking the wrong mask wastes addresses or leaves too few usable hosts. Exam questions test whether you can apply CIDR notation, calculate block size, and identify the correct usable-host range for a given prefix.
What to study next
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Malware, Social Engineering and Network Attacks — study guide chapter
Learn the concepts, then practise the questions
Malware, Social Engineering and Network Attacks practice questions
Targeted practice on this topic area only
All CEH questions
1,010 questions across all exam domains
Certified Ethical Hacker CEH study guide
Full concept coverage aligned to exam objectives
CEH practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Practise CEH questions linked to Footprinting, Reconnaissance and Scanning.
Practise CEH questions linked to Enumeration and System Hacking.
Practise CEH questions linked to Malware, Social Engineering and Network Attacks.
Practise CEH questions linked to Web Application and Injection Attacks.
Practise CEH questions linked to Introduction to Ethical Hacking.
Practise CEH questions linked to Scanning Networks and Enumeration.
Practise CEH questions linked to Vulnerability Analysis and System Hacking.
Practise CEH questions linked to Advanced Topics: Wireless, Cloud, IoT, Cryptography.
Practise CEH questions linked to Footprinting and Reconnaissance.
Practise CEH questions linked to Network and Web Application Attacks.
Practise CEH questions linked to Wireless, IoT and Cloud Security.
Practise CEH questions linked to Cryptography and Malware Analysis.
Practice this exam
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Malware, Social Engineering and Network Attacks — This question tests Malware, Social Engineering and Network Attacks — Read the scenario before looking for a memorised answer..
The correct answer is: MAC flooding — MAC flooding exploits the limited size of a switch's Content Addressable Memory (CAM) table. By sending thousands of packets with unique, fake source MAC addresses, the attacker fills the CAM table, forcing the switch to fail open and broadcast all incoming frames to every port, effectively behaving like a hub. This allows the attacker to capture traffic not originally destined for their port.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Last reviewed: Jun 30, 2026
This CEH practice question is part of Courseiva's free EC-Council certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the CEH exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.