← DEA-C01·Amazon Web Services

Question 1,366 of 1,786

Data Security and Governance →mediumMultiple ChoiceObjective-mapped

Least Privilege KMS Decrypt for Glue Jobs: Specific Key ARN

This DEA-C01 practice question tests your understanding of data security and governance. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. 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 financial services company uses AWS Glue ETL jobs to process sensitive customer data stored in Amazon S3. The data is encrypted at rest with SSE-KMS using a customer-managed key. Recently, the security team discovered that the Glue job's IAM role has an overly permissive policy that allows the 'kms:Decrypt' action for all KMS keys in the account. The company wants to follow the principle of least privilege. The Glue job runs on a schedule and reads from a specific S3 bucket. The security team needs to update the IAM policy to restrict KMS decryption to only the specific key used for that bucket. What should they do?

Clue words in this question

Noticing these words before you look at the options changes how you read each choice.

Clue: "least"
Why it matters: You want the option with minimum overhead, fewest steps, or lowest impact — not the most feature-rich or comprehensive answer.

A
Update the policy to allow 'kms:Decrypt' with a resource of 'arn:aws:kms:us-east-1:123456789012:key/*' to cover all keys in the account.
Why wrong: Incorrect. Using a wildcard in the key ARN (key/*) still grants access to all keys under that key hierarchy, which is overly permissive. The specific key ARN should be used.
B
Update the policy to allow 'kms:Decrypt' with a resource of '*' to ensure the job can always decrypt data.
Why wrong: Incorrect. Allowing 'kms:Decrypt' with resource '*' would grant access to all keys in the account, violating the principle of least privilege.
C
Update the policy to allow 'kms:Decrypt' only for the specific KMS key ARN used by the S3 bucket containing the customer data.
Correct. To follow least privilege, the IAM role should only have 'kms:Decrypt' permission on the exact ARN of the KMS key used to encrypt the S3 bucket.
D
Remove the 'kms:Decrypt' action from the policy and rely on S3 bucket policies to grant decryption permissions.
Why wrong: Incorrect. Removing 'kms:Decrypt' from the IAM policy would prevent the Glue job from decrypting the data. S3 bucket policies can grant access to the role but cannot delegate KMS decryption; the IAM role must have the permission.

Full breakdown with real-world context →

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

✓

Update the policy to allow 'kms:Decrypt' only for the specific KMS key ARN used by the S3 bucket containing the customer data.

Option C is correct. To follow least privilege, the IAM role for the Glue job should only have access to decrypt using the specific KMS key that encrypts the S3 bucket containing the customer data. This is done by allowing 'kms:Decrypt' with a resource set to the exact ARN of that key, not a wildcard or all keys. Option A is incorrect because using a wildcard in the key ARN (key/*) still grants access to all keys under that key hierarchy, which is overly permissive. Option B is incorrect because allowing 'kms:Decrypt' with resource '*' would grant access to all keys in the account, violating least privilege. Option D is incorrect because removing 'kms:Decrypt' from the IAM policy would prevent the Glue job from decrypting the data; the job's IAM role needs the permission, and relying solely on S3 bucket policies cannot grant decryption permissions cross-account or for IAM roles.

Key principle: Authentication proves identity; authorization controls what that identity can do after login. Both must work for full privileged access.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
Update the policy to allow 'kms:Decrypt' with a resource of 'arn:aws:kms:us-east-1:123456789012:key/*' to cover all keys in the account.
Why it's wrong here
Incorrect. Using a wildcard in the key ARN (key/*) still grants access to all keys under that key hierarchy, which is overly permissive. The specific key ARN should be used.
✗
Update the policy to allow 'kms:Decrypt' with a resource of '*' to ensure the job can always decrypt data.
Why it's wrong here
Incorrect. Allowing 'kms:Decrypt' with resource '*' would grant access to all keys in the account, violating the principle of least privilege.
✓
Update the policy to allow 'kms:Decrypt' only for the specific KMS key ARN used by the S3 bucket containing the customer data.
Why this is correct
Correct. To follow least privilege, the IAM role should only have 'kms:Decrypt' permission on the exact ARN of the KMS key used to encrypt the S3 bucket.
Clue confirmation
The clue word "least" in the question point toward this answer.
Related concept
Authentication checks who the user is.
✗
Remove the 'kms:Decrypt' action from the policy and rely on S3 bucket policies to grant decryption permissions.
Why it's wrong here
Incorrect. Removing 'kms:Decrypt' from the IAM policy would prevent the Glue job from decrypting the data. S3 bucket policies can grant access to the role but cannot delegate KMS decryption; the IAM role must have the permission.

Common exam traps

Common exam trap: authentication is not authorization

Logging in proves the user can authenticate. It does not automatically mean the user is allowed to enter privileged or configuration mode. Watch for AAA authorization, privilege level and command authorization details.

Detailed technical explanation

How to think about this question

This kind of question is testing the difference between identity and permission. A user may successfully log in to a router because authentication is working, but still fail to enter configuration mode because authorization is missing, misconfigured or mapped to a lower privilege level.

KKey Concepts to Remember

Authentication checks who the user is.
Authorization controls what the user is allowed to do after login.
Privilege levels affect access to EXEC and configuration commands.
AAA, TACACS+ and RADIUS can separate login success from command access.

TExam Day Tips

Do not assume successful login means full administrative access.
Look for words such as cannot enter configuration mode, privilege level, authorization or command access.
Separate login problems from permission problems before choosing the answer.

Key takeaway

Authentication proves identity; authorization controls what that identity can do after login. Both must work for full privileged access.

Real-world example

How this comes up in practice

A media company stores terabytes of video archives that are accessed once a year for audit purposes. Moving these objects to a cold storage tier (Azure Archive, S3 Glacier, or Google Nearline) costs a fraction of hot storage. Questions like this test whether you understand storage tiers, access frequency tradeoffs, and retrieval latency requirements.

Quick reference

AWS S3 Storage Class Comparison

Storage Class	Min Duration	Retrieval	Use Case
S3 Standard	None	Immediate	Frequently accessed data
S3 Standard-IA	30 days	Immediate	Infrequent access, rapid retrieval
S3 One Zone-IA	30 days	Immediate	Non-critical infrequent data
S3 Intelligent-Tiering	None	Immediate–hours	Unknown or changing access patterns
S3 Glacier Instant	90 days	Milliseconds	Archive with instant retrieval
S3 Glacier Flexible	90 days	Minutes–hours	Archive, flexible retrieval
S3 Glacier Deep Archive	180 days	Hours	Long-term compliance archive

What to study next

Got this wrong? Here's your next step.

Review Cisco AAA concepts — authentication, authorization, and accounting. Study privilege levels (0–15), command authorization under TACACS+, and how RADIUS differs. Then practise related DEA-C01 questions on access control and AAA configuration.

Related DEA-C01 practice-question pages

Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.

Data Ingestion and Transformation practice questions

Practise DEA-C01 questions linked to Data Ingestion and Transformation.

Data Operations and Support practice questions

Practise DEA-C01 questions linked to Data Operations and Support.

Data Security and Governance practice questions

Practise DEA-C01 questions linked to Data Security and Governance.

Data Store Management practice questions

Practise DEA-C01 questions linked to Data Store Management.

DEA-C01 fundamentals practice questions

Practise DEA-C01 questions linked to DEA-C01 fundamentals.

DEA-C01 scenario practice questions

Practise DEA-C01 questions linked to DEA-C01 scenario.

DEA-C01 troubleshooting practice questions

Practise DEA-C01 questions linked to DEA-C01 troubleshooting.

Practice this exam

Start a free DEA-C01 practice session

Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.

10 questions 20 questions 30 questions 50 questions Timed 30

DEA-C01 practice-test guide →Study guide →Browse all practice tests

FAQ

Questions learners often ask

What does this DEA-C01 question test?

Data Security and Governance — This question tests Data Security and Governance — Authentication checks who the user is..

What is the correct answer to this question?

The correct answer is: Update the policy to allow 'kms:Decrypt' only for the specific KMS key ARN used by the S3 bucket containing the customer data. — Option C is correct. To follow least privilege, the IAM role for the Glue job should only have access to decrypt using the specific KMS key that encrypts the S3 bucket containing the customer data. This is done by allowing 'kms:Decrypt' with a resource set to the exact ARN of that key, not a wildcard or all keys. Option A is incorrect because using a wildcard in the key ARN (key/*) still grants access to all keys under that key hierarchy, which is overly permissive. Option B is incorrect because allowing 'kms:Decrypt' with resource '*' would grant access to all keys in the account, violating least privilege. Option D is incorrect because removing 'kms:Decrypt' from the IAM policy would prevent the Glue job from decrypting the data; the job's IAM role needs the permission, and relying solely on S3 bucket policies cannot grant decryption permissions cross-account or for IAM roles.

What should I do if I get this DEA-C01 question wrong?

Are there clue words in this question I should notice?

Yes — watch for: "least". You want the option with minimum overhead, fewest steps, or lowest impact — not the most feature-rich or comprehensive answer.

What is the key concept behind this question?

Authentication checks who the user is.

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 →

How Courseiva writes practice questions · Editorial policy

Keep practising

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.

Loading comments…

This DEA-C01 practice question is part of Courseiva's free Amazon Web Services 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 DEA-C01 exam.