The correct answer is an RDP brute-force attack, because the exhibit shows repeated failed authentication attempts targeting TCP port 3389, which is the default port for Remote Desktop Protocol. A brute force attack on RDP involves systematically trying many username and password combinations to gain unauthorized remote access to a Windows system, and the port number is the key technical clue. On the CompTIA ITF+ FC0-U61 exam, this question tests your ability to map a specific port number to its associated service and recognize the pattern of a brute force attack versus other threats like a denial-of-service or malware infection. A common trap is confusing port 3389 with SSH on port 22 or HTTP on port 80, so always associate RDP with remote Windows administration. Memory tip: think “3389” as “three-three-eight-nine” — the “three” reminds you of “RDP” (Remote Desktop Protocol) and the “nine” sounds like “nine lives” of login attempts.
FC0-U61 Security Practice Question
This FC0-U61 practice question tests your understanding of 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.
Exhibit
Refer to the exhibit.
```
Event ID: 4625
Time: 2023-08-15 14:23:45
Account Name: jsmith
Failure Reason: Unknown user name or bad password.
Workstation Name: WORKSTATION-05
Logon Type: 10 (RemoteInteractive)
```
A help desk technician receives an alert from the security monitoring system showing multiple events like the one in the exhibit. The technician is investigating a possible brute-force attack. Based on the exhibit, which of the following is the primary attack vector being used?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "primary"
Why it matters: Asks for the main purpose or function, not a secondary benefit. Eliminate answers that describe side-effects or partial functions.
Refer to the exhibit.
```
Event ID: 4625
Time: 2023-08-15 14:23:45
Account Name: jsmith
Failure Reason: Unknown user name or bad password.
Workstation Name: WORKSTATION-05
Logon Type: 10 (RemoteInteractive)
```
A
VPN brute-force attack
Why wrong: VPN logon events have different logon types (e.g., 3 for network) and are not shown here.
B
RDP brute-force attack
Logon Type 10 indicates a remote interactive logon, commonly used by RDP.
C
SSH brute-force attack
Why wrong: SSH uses Logon Type 2 or 10 but typically on port 22; RDP is more common for Windows systems.
D
Web application attack
Why wrong: Web application attacks are typically seen in HTTP logs, not Windows security event logs.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
RDP brute-force attack
The exhibit shows repeated failed authentication attempts targeting TCP port 3389, which is the default port for Remote Desktop Protocol (RDP). A brute-force attack on RDP involves systematically trying many username/password combinations to gain unauthorized remote access to a Windows system. This matches the definition of an RDP brute-force attack.
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.
✗
VPN brute-force attack
Why it's wrong here
VPN logon events have different logon types (e.g., 3 for network) and are not shown here.
✓
RDP brute-force attack
Why this is correct
Logon Type 10 indicates a remote interactive logon, commonly used by RDP.
Clue confirmation
The clue word "primary" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
✗
SSH brute-force attack
Why it's wrong here
SSH uses Logon Type 2 or 10 but typically on port 22; RDP is more common for Windows systems.
✗
Web application attack
Why it's wrong here
Web application attacks are typically seen in HTTP logs, not Windows security event logs.
Common exam traps
Common exam trap: answer the scenario, not the keyword
CompTIA often tests the association of default port numbers with specific protocols, so the trap here is confusing RDP (port 3389) with SSH (port 22) or VPN (various ports), leading candidates to pick a plausible but incorrect attack vector.
Trap categories for this question
Command / output trap
VPN logon events have different logon types (e.g., 3 for network) and are not shown here.
Detailed technical explanation
How to think about this question
RDP uses TCP port 3389 by default and relies on the CredSSP protocol for authentication, which is vulnerable to brute-force attacks if weak passwords are used. In real-world scenarios, attackers often use tools like Hydra or Medusa to automate login attempts, and Windows Event ID 4625 (failed logon) is commonly logged for each attempt. Defenders can mitigate this by implementing account lockout policies, Network Level Authentication (NLA), or RDP gateway restrictions.
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 small business has 20 workstations on the 192.168.1.0/24 network and one public IP from its ISP. The router uses PAT (NAT overload) so all 20 devices share one public address using different source ports. NAT questions test whether you understand the four address terms and which direction each translation applies.
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.
Security — This question tests Security — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: RDP brute-force attack — The exhibit shows repeated failed authentication attempts targeting TCP port 3389, which is the default port for Remote Desktop Protocol (RDP). A brute-force attack on RDP involves systematically trying many username/password combinations to gain unauthorized remote access to a Windows system. This matches the definition of an RDP brute-force attack.
What should I do if I get this FC0-U61 question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Are there clue words in this question I should notice?
Yes — watch for: "primary". Asks for the main purpose or function, not a secondary benefit. Eliminate answers that describe side-effects or partial functions.
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 →
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. Based on the exhibit, which type of attack is most likely occurring?
hard
A.Denial-of-service attack
B.Phishing attack
✓ C.Brute force attack
D.Man-in-the-middle attack
Why C: The exhibit shows repeated login attempts with different passwords (e.g., 'password1', 'password2', 'password3') against a single user account. This pattern of systematically trying many passwords to guess credentials is the hallmark of a brute force attack. Unlike a denial-of-service or phishing attack, the goal here is to gain unauthorized access by exhausting possible password combinations.
Last reviewed: Jun 30, 2026
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This FC0-U61 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 FC0-U61 exam.
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