- A
Man-in-the-middle
A man-in-the-middle attack precisely describes an attacker intercepting and modifying communications between two endpoints without their knowledge.
- B
ARP spoofing
Why wrong: ARP spoofing is a technique often used to execute a man-in-the-middle attack, but it does not inherently involve modifying data; it only redirects traffic. The question describes the broader attack type.
- C
DNS poisoning
Why wrong: DNS poisoning corrupts DNS caches to redirect traffic to malicious sites, but it does not directly allow the attacker to modify the intercepted data.
- D
Replay attack
Why wrong: A replay attack captures legitimate data and retransmits it later; it does not involve real-time interception or modification.
Question 187 of 520
N10-009 Network Security Practice Question
This N10-009 practice question tests your understanding of network security. 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.
An attacker intercepts communication between two parties and is able to modify the data in transit without either party's knowledge. Which type of attack is this?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Man-in-the-middle
A man-in-the-middle (MITM) attack occurs when an adversary secretly intercepts and potentially alters the communication between two parties who believe they are directly communicating with each other. The attacker can modify data in transit without either party's knowledge by placing themselves in the logical or physical path of the data flow, often by exploiting weaknesses in authentication or encryption. This matches the scenario described, where the attacker both intercepts and modifies the data.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Man-in-the-middle
Why this is correct
A man-in-the-middle attack precisely describes an attacker intercepting and modifying communications between two endpoints without their knowledge.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
ARP spoofing
Why it's wrong here
ARP spoofing is a technique often used to execute a man-in-the-middle attack, but it does not inherently involve modifying data; it only redirects traffic. The question describes the broader attack type.
When this WOULD be correct
A question that asks: 'An attacker sends forged ARP messages to associate their MAC address with the IP address of a default gateway, causing traffic to be redirected through the attacker's machine. Which type of attack is this?' would make ARP spoofing the correct answer.
- ✗
DNS poisoning
Why it's wrong here
DNS poisoning corrupts DNS caches to redirect traffic to malicious sites, but it does not directly allow the attacker to modify the intercepted data.
When this WOULD be correct
A question describing an attack where users are redirected to a fake website that mimics a legitimate one, and the attacker captures credentials or serves malware, would make DNS poisoning the correct answer.
- ✗
Replay attack
Why it's wrong here
A replay attack captures legitimate data and retransmits it later; it does not involve real-time interception or modification.
When this WOULD be correct
A replay attack would be correct if the question described an attacker capturing authentication tokens or session data and reusing them to impersonate a user, without any modification of the data.
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The N10-009 exam frequently reuses these exact scenarios with slightly different constraints.
✓Man-in-the-middleCorrect answer▾
Why this is correct
A man-in-the-middle attack precisely describes an attacker intercepting and modifying communications between two endpoints without their knowledge.
✗ARP spoofingWrong answer — click to see why▾
Why this is wrong here
ARP spoofing is a technique used to associate an attacker's MAC address with the IP address of a legitimate device, enabling interception of traffic, but it does not inherently involve modifying data in transit. The question specifies modification of data, which is a key characteristic of a man-in-the-middle attack, not ARP spoofing alone.
★ When this WOULD be the correct answer
A question that asks: 'An attacker sends forged ARP messages to associate their MAC address with the IP address of a default gateway, causing traffic to be redirected through the attacker's machine. Which type of attack is this?' would make ARP spoofing the correct answer.
Why candidates choose this
Candidates may confuse ARP spoofing with man-in-the-middle because ARP spoofing is often used as a precursor to a man-in-the-middle attack, leading them to incorrectly select it as the primary attack type when the question focuses on data modification.
✗DNS poisoningWrong answer — click to see why▾
Why this is wrong here
DNS poisoning involves corrupting DNS resolver caches to redirect traffic to malicious sites, but it does not inherently allow real-time modification of data in transit between two parties.
★ When this WOULD be the correct answer
A question describing an attack where users are redirected to a fake website that mimics a legitimate one, and the attacker captures credentials or serves malware, would make DNS poisoning the correct answer.
Why candidates choose this
Candidates may confuse DNS poisoning with man-in-the-middle because both can intercept traffic, but they overlook that DNS poisoning redirects traffic rather than modifying data in an existing session.
✗Replay attackWrong answer — click to see why▾
Why this is wrong here
A replay attack involves capturing and retransmitting valid data, but it does not allow the attacker to modify data in transit without detection. The question specifies modification, which is a key feature of man-in-the-middle attacks.
★ When this WOULD be the correct answer
A replay attack would be correct if the question described an attacker capturing authentication tokens or session data and reusing them to impersonate a user, without any modification of the data.
Why candidates choose this
Candidates may confuse replay attacks with man-in-the-middle because both involve intercepting communications, but they overlook that replay attacks do not involve altering the data.
Analysis generated from the official N10-009blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Common exam traps
Common exam trap: answer the scenario, not the keyword
The N10-009 exam often tests the distinction between the attack type (MITM) and the technique used to achieve it (ARP spoofing, DNS poisoning), so candidates mistakenly select the technique rather than the overarching attack described in the scenario.
Detailed technical explanation
How to think about this question
In a classic MITM attack, the attacker often uses ARP spoofing to intercept traffic on a switched Ethernet network, then forwards packets after modification. For encrypted sessions, the attacker may perform SSL stripping or present a forged certificate to decrypt and re-encrypt traffic, as seen in tools like ettercap or bettercap. The attack exploits the lack of mutual authentication or integrity checks at the transport layer, which is why protocols like TLS with certificate pinning or SSH with host key verification are critical defenses.
KKey Concepts to Remember
- Read the scenario before looking for a memorised answer.
- Find the constraint that changes the correct option.
- Eliminate answers that are true in general but not in this case.
TExam Day Tips
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A practitioner preparing for the N10-009 exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
- →
Network Security — study guide chapter
Learn the concepts, then practise the questions
- →
Network Security practice questions
Targeted practice on this topic area only
- →
All N10-009 questions
520 questions across all exam domains
- →
CompTIA Network+ N10-009 study guide
Full concept coverage aligned to exam objectives
- →
N10-009 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related N10-009 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Networking Concepts practice questions
Practise N10-009 questions linked to Networking Concepts.
Network Implementation practice questions
Practise N10-009 questions linked to Network Implementation.
Network Operations practice questions
Practise N10-009 questions linked to Network Operations.
Network Security practice questions
Practise N10-009 questions linked to Network Security.
Network Troubleshooting practice questions
Practise N10-009 questions linked to Network Troubleshooting.
Network+ network fundamentals practice questions
Practise N10-009 questions linked to Network+ network fundamentals.
Practice this exam
Start a free N10-009 practice session
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Questions learners often ask
What does this N10-009 question test?
Network Security — This question tests Network Security — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Man-in-the-middle — A man-in-the-middle (MITM) attack occurs when an adversary secretly intercepts and potentially alters the communication between two parties who believe they are directly communicating with each other. The attacker can modify data in transit without either party's knowledge by placing themselves in the logical or physical path of the data flow, often by exploiting weaknesses in authentication or encryption. This matches the scenario described, where the attacker both intercepts and modifies the data.
What should I do if I get this N10-009 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
What is the key concept behind this question?
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 →
Keep practising
More N10-009 practice questions
- Which of the following network devices operates primarily at Layer 2 of the OSI model and uses MAC addresses to forward…
- Which of the following is a characteristic of UDP when compared to TCP?
- Which of the following IPv6 addresses is a valid link-local address?
- Which of the following security mechanisms requires a user to authenticate before gaining access to the wired network at…
- Which of the following network protocols operates at the Transport layer of the OSI model and provides connection-orient…
- Which of the following is a characteristic of a connectionless protocol at the transport layer?
Last reviewed: Jun 11, 2026
This N10-009 practice question is part of Courseiva's free CompTIA 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 N10-009 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.