- A
securityContext: capabilities: drop: ["ALL"] add: ["ALL"]
Why wrong: Adding ALL after dropping ALL is pointless; it grants all capabilities again.
- B
securityContext: capabilities: drop: ["ALL"] add: ["NET_BIND_SERVICE"]
Correctly drops all capabilities then adds only the needed one, following the principle of least privilege.
- C
securityContext: capabilities: drop: ["CHOWN","DAC_OVERRIDE"]
Why wrong: This only drops two specific capabilities, not all. The policy requires dropping all capabilities first.
- D
securityContext: capabilities: add: ["NET_BIND_SERVICE"] drop: ["ALL"]
Why wrong: The order in the YAML does not matter; however, it is conventional to drop first then add. But functionally this is correct if drop ALL is included. However, option D is more explicit and common.
Drop All Capabilities and Add Specific — Understanding Order | Certified Kubernetes Security Specialist Explained
This CKS practice question tests your understanding of system hardening. Match the stated requirement to the specific cloud service, access model, or configuration option — many options are valid in isolation but not for this scenario. 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 security policy requires that containers should drop all capabilities and only add back the specific capabilities needed. Which YAML snippet correctly implements this for a container?
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
securityContext: capabilities: drop: ["ALL"] add: ["NET_BIND_SERVICE"]
Option B is correct because it first drops all capabilities with `drop: ["ALL"]` and then adds back only the specific capability needed (`NET_BIND_SERVICE`). In Kubernetes, the `add` and `drop` fields are processed sequentially: `add` is applied to the default capabilities first, then `drop` removes capabilities. Therefore, if you add before dropping all, as in option D, the added capability is also dropped, resulting in an empty set. The order matters, and only the drop-first-then-add sequence achieves the intended final set of capabilities.
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.
- ✗
securityContext: capabilities: drop: ["ALL"] add: ["ALL"]
Why it's wrong here
Adding ALL after dropping ALL is pointless; it grants all capabilities again.
- ✓
securityContext: capabilities: drop: ["ALL"] add: ["NET_BIND_SERVICE"]
Why this is correct
Correctly drops all capabilities then adds only the needed one, following the principle of least privilege.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
securityContext: capabilities: drop: ["CHOWN","DAC_OVERRIDE"]
Why it's wrong here
This only drops two specific capabilities, not all. The policy requires dropping all capabilities first.
- ✗
securityContext: capabilities: add: ["NET_BIND_SERVICE"] drop: ["ALL"]
Why it's wrong here
The order in the YAML does not matter; however, it is conventional to drop first then add. But functionally this is correct if drop ALL is included. However, option D is more explicit and common.
Common exam traps
Common exam trap: answer the scenario, not the keyword
CNCF often tests the misconception that the order of `add` and `drop` in the YAML matters, or that dropping only a few capabilities is sufficient, when the policy explicitly requires dropping all capabilities first and then adding back only what is needed.
Detailed technical explanation
How to think about this question
Under the hood, Linux capabilities are implemented as bitmaps in the kernel's task struct; dropping `ALL` clears the effective, permitted, and inheritable capability sets, and adding specific capabilities sets the corresponding bits. In Kubernetes, the `securityContext.capabilities` field modifies the container's capability bounding set via the `capabilities(7)` system calls, and the order of `drop` and `add` in the YAML is irrelevant because the kubelet merges them into a single operation. A real-world scenario is a web server that needs to bind to a privileged port (<1024) but should not have any other elevated privileges, making `NET_BIND_SERVICE` the only capability required.
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 CKS 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.
- →
System Hardening — study guide chapter
Learn the concepts, then practise the questions
- →
System Hardening practice questions
Targeted practice on this topic area only
- →
All CKS questions
997 questions across all exam domains
- →
Certified Kubernetes Security Specialist CKS study guide
Full concept coverage aligned to exam objectives
- →
CKS practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related CKS practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Monitoring Logging and Runtime Security practice questions
Practise CKS questions linked to Monitoring Logging and Runtime Security.
Cluster Setup and Hardening practice questions
Practise CKS questions linked to Cluster Setup and Hardening.
System Hardening practice questions
Practise CKS questions linked to System Hardening.
Minimize Microservice Vulnerabilities practice questions
Practise CKS questions linked to Minimize Microservice Vulnerabilities.
Supply Chain Security practice questions
Practise CKS questions linked to Supply Chain Security.
Monitoring, Logging and Runtime Security practice questions
Practise CKS questions linked to Monitoring, Logging and Runtime Security.
Cluster Setup practice questions
Practise CKS questions linked to Cluster Setup.
Cluster Hardening practice questions
Practise CKS questions linked to Cluster Hardening.
CKS fundamentals practice questions
Practise CKS questions linked to CKS fundamentals.
CKS scenario practice questions
Practise CKS questions linked to CKS scenario.
CKS troubleshooting practice questions
Practise CKS questions linked to CKS troubleshooting.
Practice this exam
Start a free CKS 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 CKS question test?
System Hardening — This question tests System Hardening — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: securityContext: capabilities: drop: ["ALL"] add: ["NET_BIND_SERVICE"] — Option B is correct because it first drops all capabilities with `drop: ["ALL"]` and then adds back only the specific capability needed (`NET_BIND_SERVICE`). In Kubernetes, the `add` and `drop` fields are processed sequentially: `add` is applied to the default capabilities first, then `drop` removes capabilities. Therefore, if you add before dropping all, as in option D, the added capability is also dropped, resulting in an empty set. The order matters, and only the drop-first-then-add sequence achieves the intended final set of capabilities.
What should I do if I get this CKS 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 →
Same concept, more angles
1 more ways this is tested on CKS
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 container is running with the following securityContext: securityContext: capabilities: drop: ["ALL"] add: ["NET_BIND_SERVICE"] Which capabilities will the container have?
medium- A.All capabilities except NET_BIND_SERVICE
- ✓ B.Only NET_BIND_SERVICE
- C.No capabilities
- D.All default capabilities plus NET_BIND_SERVICE
Why B: The securityContext first drops all capabilities with `drop: ["ALL"]`, which removes every capability from the container's bounding set. Then `add: ["NET_BIND_SERVICE"]` adds back only that single capability. Therefore, the final effective set is exactly `NET_BIND_SERVICE`, making option B correct.
Keep practising
More CKS practice questions
- Which flag is used to restrict the kubelet's ability to modify node status and pods?
- A Falco rule has priority `WARNING` and output: `Sensitive file opened (user=%user.name command=%proc.cmdline file=%fd.n…
- Falco detects a shell being opened inside a container. Which Falco rule field is used to specify the syscall condition f…
- A security audit reveals that a ServiceAccount named 'monitor' has a ClusterRoleBinding to the cluster-admin role. What…
- Match each Kubernetes security component to its description.
- Match each Kubernetes certificate type to its usage.
Last reviewed: Jun 30, 2026
This CKS practice question is part of Courseiva's free CNCF 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 CKS 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.