The correct answer is least privilege, as allowing root login via SSH directly violates this principle by granting unrestricted administrative access without requiring any privilege escalation. In a properly hardened SSH configuration, root login should be disabled—typically by setting `PermitRootLogin no` in `/etc/ssh/sshd_config`—forcing administrators to log in as a regular user and then use `sudo` or `su` to elevate privileges only when necessary. This minimizes the attack surface and ensures all actions are auditable and tied to a specific user account. On the ISC2 Certified in Cybersecurity CC exam, this concept tests your understanding of access control fundamentals; a common trap is confusing least privilege with separation of duties or defense in depth. Remember the memory tip: “No root SSH—escalate to elevate.”
ISC2 CC Security Principles Practice Question
This CC practice question tests your understanding of security principles. 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.
Exhibit
Refer to the exhibit.
```
Oct 15 10:23:45 server sshd[1234]: Failed password for root from 192.168.1.100 port 22 ssh2
Oct 15 10:23:46 server sshd[1234]: Failed password for root from 192.168.1.100 port 22 ssh2
Oct 15 10:23:47 server sshd[1234]: Failed password for root from 192.168.1.100 port 22 ssh2
Oct 15 10:23:48 server sshd[1234]: Failed password for root from 192.168.1.100 port 22 ssh2
Oct 15 10:23:49 server sshd[1234]: Failed password for root from 192.168.1.100 port 22 ssh2
```
An analyst reviews the exhibit. Which security principle is being violated by allowing root login via SSH?
Refer to the exhibit.
```
Oct 15 10:23:45 server sshd[1234]: Failed password for root from 192.168.1.100 port 22 ssh2
Oct 15 10:23:46 server sshd[1234]: Failed password for root from 192.168.1.100 port 22 ssh2
Oct 15 10:23:47 server sshd[1234]: Failed password for root from 192.168.1.100 port 22 ssh2
Oct 15 10:23:48 server sshd[1234]: Failed password for root from 192.168.1.100 port 22 ssh2
Oct 15 10:23:49 server sshd[1234]: Failed password for root from 192.168.1.100 port 22 ssh2
```
A
Fail-safe
Why wrong: Fail-safe is not relevant.
B
Least privilege
Correct. Root should not be allowed to log in directly.
C
Defense in depth
Why wrong: Defense in depth is about multiple layers, not this issue.
D
Separation of duties
Why wrong: Separation of duties is not directly related.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Least privilege
Allowing root login via SSH violates the principle of least privilege because it grants unrestricted administrative access to the system, bypassing any need for privilege escalation. In a properly secured SSH configuration, root login should be disabled (e.g., `PermitRootLogin no` in `/etc/ssh/sshd_config`), forcing administrators to log in as a regular user and then use `sudo` or `su` to elevate privileges only when necessary. This minimizes the attack surface and ensures that actions are auditable and tied to a specific user account.
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.
✗
Fail-safe
Why it's wrong here
Fail-safe is not relevant.
✓
Least privilege
Why this is correct
Correct. Root should not be allowed to log in directly.
Related concept
Read the scenario before looking for a memorised answer.
✗
Defense in depth
Why it's wrong here
Defense in depth is about multiple layers, not this issue.
✗
Separation of duties
Why it's wrong here
Separation of duties is not directly related.
Common exam traps
Common exam trap: answer the scenario, not the keyword
ISC2 often tests the distinction between least privilege and defense in depth, where candidates mistakenly choose defense in depth because they think multiple security layers are involved, but the question specifically targets the principle of granting only the minimum necessary access.
Detailed technical explanation
How to think about this question
Under the hood, SSH authentication with root login enabled means the root account can authenticate directly via password or public key, bypassing any audit trail of which user performed actions. Even with `PermitRootLogin prohibit-password` (allowing key-based root login), the risk remains that a compromised root key grants full system control without any intermediate user accountability. In real-world scenarios, compliance frameworks like PCI DSS explicitly require disabling direct root login to enforce non-repudiation and traceability.
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 analyst at a medium-sized enterprise encounters this scenario during an investigation or architecture review. The correct answer reflects best practice for the specific threat or control described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Security exam questions test whether you can match controls to threats in context — not just recall definitions.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this CC question in full detail.
Security Principles — This question tests Security Principles — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Least privilege — Allowing root login via SSH violates the principle of least privilege because it grants unrestricted administrative access to the system, bypassing any need for privilege escalation. In a properly secured SSH configuration, root login should be disabled (e.g., `PermitRootLogin no` in `/etc/ssh/sshd_config`), forcing administrators to log in as a regular user and then use `sudo` or `su` to elevate privileges only when necessary. This minimizes the attack surface and ensures that actions are auditable and tied to a specific user account.
What should I do if I get this CC 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 →
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. A security administrator notices that a user with standard privileges was able to modify a system file. Which security principle has been violated?
easy
A.Need to know
B.Defense in depth
✓ C.Least privilege
D.Separation of duties
Why C: The principle of least privilege requires that users be granted only the permissions necessary to perform their job functions. A standard user modifying a system file indicates they have been assigned unnecessary administrative rights, violating this principle. This could occur if the user is a member of a group like Administrators or has been granted explicit write access to protected directories such as %SystemRoot%\System32.
Variation 2. A security analyst discovers that an organization's firewall rule set allows all inbound traffic on TCP port 443 from any source to a single web server. Additionally, the server has a known critical vulnerability in its TLS implementation. Which principle of security architecture is most directly violated by this configuration?
hard
✓ A.Least privilege
B.Defense in depth
C.Separation of duties
D.Fail-safe defaults
Why A: Least privilege requires restricting access to only what is necessary. Allowing inbound from any source (0.0.0.0/0) violates least privilege because it is broader than necessary. Option B is correct. Option A (defense in depth) would be violated if no other controls exist, but the question asks the most direct violation. Option C (separation of duties) is about task division. Option D (fail-safe) is about default deny.
Last reviewed: Jun 30, 2026
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This CC practice question is part of Courseiva's free ISC2 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 CC exam.
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