SCS-C02 Data Protection Practice Question
A company uses AWS KMS to encrypt data in Amazon S3. The security team receives an alert that an IAM user is attempting to decrypt data using a key that they do not have access to. Which AWS service can be used to monitor and alert on such unauthorized KMS API calls?
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
✓
AWS CloudTrail with CloudWatch Alarms
AWS CloudTrail logs all KMS API calls, and CloudWatch Alarms can be configured to trigger on specific unauthorized API calls, such as Decrypt attempts with a key the user does not have access to. Option A is incorrect because Amazon GuardDuty is a threat detection service that focuses on identifying malicious activity, but it does not provide detailed monitoring of specific KMS API calls. Option B is incorrect because AWS Config evaluates resource configurations and compliance, not API calls. Option D is incorrect because Amazon Inspector is a vulnerability assessment service for EC2 instances and does not monitor API calls.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Amazon GuardDuty
Why it's wrong here
Amazon GuardDuty is a continuous threat detection service that ingests AWS CloudTrail management events, VPC flow logs, and DNS query logs to identify malicious activity, but it does not provide configurable, event-driven alerting on individual KMS API operations such as kms:Decrypt or kms:ScheduleKeyDeletion. While GuardDuty can flag anomalies involving IAM principals with KMS permissions, it cannot be relied upon to emit a specific alarm every time a particular KMS action occurs. For that degree of control, you need CloudTrail logs combined with CloudWatch Alarms.
- ✗
AWS Config
Why it's wrong here
AWS Config is designed to record and evaluate resource configuration changes, such as alterations to a KMS key policy or changes in key rotation status, and to trigger rules for compliance. It does not ingest or process data-plane or control-plane API calls like kms:Decrypt, kms:Encrypt, or kms:PutKeyPolicy, so it cannot generate a real-time alert based on a single historical KMS API request. CloudTrail is the correct source for KMS API activity, not AWS Config.
- ✓
AWS CloudTrail with CloudWatch Alarms
Why this is correct
AWS CloudTrail captures every KMS API request as a management event, including kms:Encrypt, kms:Decrypt, and kms:ScheduleKeyDeletion, and delivers those logs to an S3 bucket. You can then define a CloudWatch Logs metric filter on the JSON field of the CloudTrail event to match a specific KMS action, and attach a CloudWatch Alarm to that metric to trigger an SNS notification. This combination provides the required trackable, alertable audit trail for KMS API calls made when S3 encrypts objects using customer-managed KMS keys.
- ✗
Amazon Inspector
Why it's wrong here
Amazon Inspector is a vulnerability management service that performs automated security assessments on EC2 instances, ECR container images, and AWS Lambda functions, checking for software vulnerabilities, unintended network exposure, and missing patches. It has no integration with KMS key usage, no visibility into AWS API call patterns, and cannot evaluate or alarm on KMS operations such as kms:Decrypt. Inspector is therefore completely unsuitable for monitoring KMS encryption activity in S3.
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 SCS-C02 question from scratch — 1,205 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 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.