- A
MaxAuthTries 6
Why wrong: Higher max tries increases brute force risk; lower is better.
- B
PasswordAuthentication no
Disables password logins, reducing risk of brute force.
- C
Protocol 1
Why wrong: Protocol 1 is insecure; should be Protocol 2 only.
- D
PermitRootLogin yes
Why wrong: Allowing root login reduces security.
- E
AllowUsers alice bob
Restricts which users can log in, reducing attack surface.
Question 824 of 981
XK0-005 Security Practice Question
This XK0-005 practice question tests your understanding of security. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. 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 Linux engineer needs to harden SSH access. Which TWO of the following settings should be configured in /etc/ssh/sshd_config to enhance security? (Select TWO.)
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
✓
PasswordAuthentication no
Option B is correct because disabling password authentication forces the use of SSH keys, which are resistant to brute-force attacks and credential stuffing. This setting eliminates the risk of weak or reused passwords being exploited, a fundamental hardening step for SSH access.
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.
- ✗
MaxAuthTries 6
Why it's wrong here
Higher max tries increases brute force risk; lower is better.
- ✓
PasswordAuthentication no
Why this is correct
Disables password logins, reducing risk of brute force.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Protocol 1
Why it's wrong here
Protocol 1 is insecure; should be Protocol 2 only.
- ✗
PermitRootLogin yes
Why it's wrong here
Allowing root login reduces security.
- ✓
AllowUsers alice bob
Why this is correct
Restricts which users can log in, reducing attack surface.
Related concept
Read the scenario before looking for a memorised answer.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often confuse 'hardening' with 'increasing limits' (like MaxAuthTries) or 'enabling convenience' (like PermitRootLogin yes), when the correct hardening choices actually restrict or disable weaker authentication methods.
Detailed technical explanation
How to think about this question
Under the hood, SSH key authentication uses asymmetric cryptography (RSA, ECDSA, or Ed25519) where the private key never traverses the network, unlike passwords which are transmitted as hashed values. In a real-world scenario, disabling password authentication is critical for internet-facing servers, as automated bots continuously attempt password-based logins; even with strong passwords, key-based authentication eliminates this entire attack vector.
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 security administrator must allow nursing staff to reach a patient records server while blocking access from the guest Wi-Fi VLAN. After applying an extended ACL, traffic is still blocked from nursing workstations. The ACL was applied outbound instead of inbound on the wrong interface. Questions like this test ACL direction and placement rules.
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.
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FAQ
Questions learners often ask
What does this XK0-005 question test?
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: PasswordAuthentication no — Option B is correct because disabling password authentication forces the use of SSH keys, which are resistant to brute-force attacks and credential stuffing. This setting eliminates the risk of weak or reused passwords being exploited, a fundamental hardening step for SSH access.
What should I do if I get this XK0-005 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.
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Last reviewed: Jul 4, 2026
This XK0-005 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 XK0-005 exam.
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