DEA-C01 SSE-KMS Practice Question
A company stores sensitive customer data in an Amazon S3 bucket. The security team requires that all data be encrypted at rest using server-side encryption with AWS KMS managed keys (SSE-KMS). Additionally, they want to ensure that the encryption context is enforced for all PutObject requests. Which THREE steps should be taken to meet these requirements?
⚠ Common exam trap
Candidates might think that SSE-C is required to enforce encryption context, but encryption context can be enforced through a bucket policy condition with kms:EncryptionContext even with SSE-KMS.
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
✓
Set the default encryption on the bucket to SSE-KMS with the desired KMS key.
To enforce SSE-KMS and encryption context, three steps are needed. First, set default encryption on the bucket to SSE-KMS with the desired KMS key (A). Second, add a bucket policy that requires the s3:x-amz-server-side-encryption-aws-kms-key-id header and the kms:EncryptionContext condition key (B). Third, ensure the IAM role used by applications has kms:GenerateDataKey and kms:Decrypt permissions for the KMS key (E). Option C (SSE-C) is incorrect because it uses a customer-provided key, not KMS. Option D (versioning) does not enforce encryption context.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Set the default encryption on the bucket to SSE-KMS with the desired KMS key.
Why this is correct
Correct. Setting default encryption to SSE-KMS ensures new objects are encrypted with the specified KMS key if no encryption header is provided.
- ✓
Add a bucket policy that requires the s3:x-amz-server-side-encryption-aws-kms-key-id header and the kms:EncryptionContext condition.
Why this is correct
Correct. Adding a bucket policy with conditions for s3:x-amz-server-side-encryption-aws-kms-key-id and kms:EncryptionContext enforces that PutObject requests include the specific KMS key and encryption context.
- ✗
Configure the bucket to use SSE-C and provide the encryption key.
Why it's wrong here
Incorrect. SSE-C uses a customer-provided key, not AWS KMS, so it does not meet the requirement for SSE-KMS.
- ✗
Enable S3 Versioning on the bucket.
Why it's wrong here
Incorrect. S3 Versioning does not relate to encryption or encryption context enforcement.
- ✓
Create an IAM role that includes kms:GenerateDataKey and kms:Decrypt permissions for the KMS key.
Why this is correct
Correct. The IAM role must have kms:GenerateDataKey and kms:Decrypt permissions to allow applications to encrypt and decrypt data using the KMS key.
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
Courseiva writes every DEA-C01 question from scratch — 1,711 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
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.