SCS-C02 Identity and Access Management Practice Question
A company has an S3 bucket that contains sensitive data. The security team wants to ensure that all objects uploaded to the bucket are encrypted at rest using server-side encryption with AWS KMS (SSE-KMS). What should the security team do to enforce this requirement?
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
✓
Use an S3 bucket policy with a condition that denies PutObject if the x-amz-server-side-encryption header is not set to 'aws:kms'.
An S3 bucket policy with a condition that denies PutObject requests unless the x-amz-server-side-encryption header is set to 'aws:kms' ensures that only objects encrypted with SSE-KMS can be uploaded. Option A is incorrect because requiring a specific KMS key ID is not necessary; the policy should enforce the use of SSE-KMS, not a specific key. Option B is incorrect because requiring the header to be present does not enforce SSE-KMS; it could be 'AES256' for SSE-S3. Option C is incorrect because default encryption only encrypts objects that lack encryption headers; it does not prevent uploads that specify SSE-S3 or no encryption.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Use an S3 bucket policy that requires the x-amz-server-side-encryption-aws-kms-key-id header to match a specific KMS key.
Why it's wrong here
While more restrictive, this does not enforce the use of SSE-KMS; an object could be encrypted with SSE-S3 and still include a KMS key ID header, causing confusion.
- ✗
Use an S3 bucket policy with a condition that requires the x-amz-server-side-encryption header to be present.
Why it's wrong here
This condition alone does not enforce a specific encryption method; it only requires the header to be present.
- ✗
Configure the bucket's default encryption to use SSE-KMS.
Why it's wrong here
Default encryption only applies when no encryption header is provided; it does not deny uploads with other encryption or without encryption.
- ✓
Use an S3 bucket policy with a condition that denies PutObject if the x-amz-server-side-encryption header is not set to 'aws:kms'.
Why this is correct
This policy denies uploads that do not use SSE-KMS, effectively enforcing the requirement.
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 |
Go deeper
Related to this question
About these practice questions
One of 376 original SCS-C02 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This SCS-C02 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 SCS-C02 exam.