Question 615 of 1,040
Design Secure ArchitecturesmediumMultiple ChoiceObjective-mapped

Quick Answer

The answer is to update the CMK key policy to explicitly include the consumer IAM role principal with kms:Decrypt permission. This is correct because KMS key policies act as the primary access control for customer-managed keys; even if an IAM role has a permissions policy allowing kms:Decrypt, the key policy must also grant that role access, or the request will be denied at the key level. On the SAA-C03 exam, this scenario tests your understanding that KMS key policies are resource-based and override IAM identity-based policies when they are missing or restrictive—a common trap is assuming IAM permissions alone are sufficient for a CMK. Remember the memory tip: "Key policy is the gatekeeper; IAM policy is the key—both are needed to unlock decrypt."

SAA-C03 Design Secure Architectures Practice Question

This SAA-C03 practice question tests your understanding of design secure architectures. 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 customer-managed KMS key (CMK) encrypts SQS messages. A consumer service uses an IAM role that includes kms:Decrypt permission for that CMK. After a security change, the consumer fails with: "AccessDeniedException: kms:Decrypt is not allowed" CloudTrail indicates the KMS request is reaching KMS, but the CMK key policy no longer includes the consumer role (or its principal). What is the best fix?

Clue words in this question

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

  • Clue: "best"

    Why it matters: Signals that multiple options may be partially correct. Choose the option that most directly solves the exact problem described, not the one that sounds most complete.

Question 1mediummultiple choice
Full question →

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 CMK key policy to allow the consumer role principal to perform kms:Decrypt on the CMK.

Option A is correct because the error indicates that the KMS key policy explicitly denies the consumer role's kms:Decrypt request. Since KMS key policies are the primary access control for CMKs, adding the consumer role principal with kms:Decrypt permission resolves the issue. The CloudTrail log confirms the request reaches KMS, so the problem is solely the missing key policy statement.

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.

  • Update the CMK key policy to allow the consumer role principal to perform kms:Decrypt on the CMK.

    Why this is correct

    For customer-managed keys, the CMK key policy is the authoritative authorization control for KMS operations. Even if the role’s identity policy allows kms:Decrypt, KMS will still deny the request unless the key policy also permits the principal (or a grant permits it).

    Clue confirmation

    The clue word "best" in the question point toward this answer.

    Related concept

    Read the scenario before looking for a memorised answer.

  • Update only the consumer role identity policy because identity policies always override key policies.

    Why it's wrong here

    Identity policies do not override a restrictive KMS key policy. KMS evaluates key policy authorization for customer-managed keys in addition to (and in practice as the gate for) identity-based permissions.

  • Enable default encryption on SQS so that KMS permissions are no longer required.

    Why it's wrong here

    SQS encryption settings do not remove the authorization requirement for decrypting with a CMK. If messages are encrypted using a CMK, kms:Decrypt must still be allowed.

  • Create an S3 bucket policy statement allowing kms:Decrypt because the messages are stored in S3.

    Why it's wrong here

    SQS message decryption authorization is evaluated by KMS using the CMK key policy (and possible grants). S3 bucket policies are unrelated to KMS authorization for SQS decryption.

Common exam traps

Common exam trap: answer the scenario, not the keyword

The trap here is that candidates assume identity policies alone are sufficient for KMS access, but KMS requires explicit authorization in the key policy unless the key policy includes a statement delegating access to IAM policies.

Trap categories for this question

  • Real-world vs exam trap

    Identity policies do not override a restrictive KMS key policy. KMS evaluates key policy authorization for customer-managed keys in addition to (and in practice as the gate for) identity-based permissions.

Detailed technical explanation

How to think about this question

KMS key policies are resource-based policies that can grant access to principals directly or delegate authorization to IAM policies via the 'Enable IAM User Permissions' statement. When a key policy does not include the consumer role's ARN, the request fails even if the role has kms:Decrypt in its identity policy, because KMS evaluates both the key policy and the identity policy, and the key policy must explicitly allow the principal. In practice, this often occurs after a security audit removes overly permissive key policy statements, inadvertently breaking cross-account or cross-service access.

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 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.

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.

Related practice questions

Related SAA-C03 practice-question pages

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

Practice this exam

Start a free SAA-C03 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 SAA-C03 question test?

Design Secure Architectures — This question tests Design Secure Architectures — Read the scenario before looking for a memorised answer..

What is the correct answer to this question?

The correct answer is: Update the CMK key policy to allow the consumer role principal to perform kms:Decrypt on the CMK. — Option A is correct because the error indicates that the KMS key policy explicitly denies the consumer role's kms:Decrypt request. Since KMS key policies are the primary access control for CMKs, adding the consumer role principal with kms:Decrypt permission resolves the issue. The CloudTrail log confirms the request reaches KMS, so the problem is solely the missing key policy statement.

What should I do if I get this SAA-C03 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: "best". Signals that multiple options may be partially correct. Choose the option that most directly solves the exact problem described, not the one that sounds most complete.

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 →

How Courseiva writes practice questions · Editorial policy

Last reviewed: Jun 11, 2026

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…

Sign in to join the discussion.

This SAA-C03 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 SAA-C03 exam.