Amazon Web Services Updated SCS-C03 Exam Questions and Answers by alvie

AWS incident response best practices emphasize isolating compromised resources rather than immediately terminating them. According to AWS Certified Security – Specialty documentation, removing an instance from an Auto Scaling group prevents replacement loops, while applying a restrictive security group isolates the instance for forensic analysis.

Using Amazon EventBridge to trigger an AWS Lambda function enables automated, consistent responses to GuardDuty findings. This approach minimizes disruption to the application because healthy instances continue serving traffic while the affected instance is isolated.

Disabling credentials or modifying network ACLs can have broader impact on unrelated workloads. SNS notifications alone do not provide response automation.

AWS recommends isolate-and-investigate patterns for EC2 incident response.

Referenced AWS Specialty Documents:

AWS Certified Security – Specialty Official Study Guide

Amazon GuardDuty Automated Responses

AWS Incident Response Playbooks

Amazon GuardDuty provides continuous monitoring for anomalous and malicious network activity by analyzing VPC Flow Logs, DNS logs, and CloudTrail events. Enabling GuardDuty across accounts requires minimal configuration and immediately satisfies the requirement to monitor endpoints for anomalous network traffic, as described in the AWS Certified Security – Specialty Study Guide.

Encrypting data in transit for applications behind Elastic Load Balancing is most efficiently achieved by using AWS Certificate Manager (ACM). ACM provisions and manages TLS certificates automatically, and integrating ACM with ELB enables encrypted communication without manual certificate management.

For encryption at rest in Amazon S3, AWS best practices recommend enforcing server-side encryption using AWS KMS. An S3 bucket policy that denies PutObject requests unless the x-amz-server-side-encryption condition is present ensures that all uploaded objects are encrypted at rest using KMS-managed keys. This provides strong encryption guarantees with minimal operational effort.

Option A is unnecessary because Amazon Inspector focuses on vulnerability assessment, not encryption or network anomaly detection. Option C adds network complexity and is not required to meet the stated requirements. Option E is incorrect because x-amz-meta-side-encryption is not a valid enforcement mechanism.

Referenced AWS Specialty Documents:

AWS Certified Security – Specialty Official Study Guide

Amazon GuardDuty Threat Detection

AWS Certificate Manager and ELB Integration

Amazon S3 Encryption Best Practices

AWS IAM Identity Center relies on SAML assertions and attribute mappings to associate federated users with identities, groups, and permission sets. According to the AWS Certified Security – Specialty documentation, when changing identity providers while maintaining the same underlying directory, existing users and group identities can be preserved by updating attribute mappings to align with the new IdP’s SAML assertions.

By modifying the attribute mappings, IAM Identity Center can correctly interpret usernames, group memberships, and unique identifiers sent by the new IdP without requiring changes to AWS account roles or permission sets. This approach minimizes operational effort and avoids disruption to access management.

Option A unnecessarily disables identities and causes access outages. Option C is incorrect because IAM Identity Center abstracts role trust relationships, and roles do not directly trust the IdP. Option D is unrelated to federation source configuration and only affects authentication timing issues.

AWS best practices recommend updating attribute mappings when switching IdPs that share the same directory source.

Referenced AWS Specialty Documents:

AWS Certified Security – Specialty Official Study Guide

AWS IAM Identity Center SAML Federation

AWS Identity Federation Best Practices

When Amazon CloudFront is used in front of an Application Load Balancer, CloudFront becomes the immediate source of incoming requests to the ALB. As a result, AWS WAF logs record theCloudFront edge location IP addressesas the client IPs, not the original viewer IP addresses. This behavior is explicitly documented in the AWS Certified Security – Specialty Study Guide and the AWS WAF and CloudFront integration documentation.

To preserve the original client IP address, CloudFront automatically adds theX-Forwarded-For HTTP header, which contains the IP address of the originating client followed by any proxy addresses involved in forwarding the request. AWS WAF logs include this header, making it the authoritative source for identifying true client IP addresses when CloudFront is used.

Option A is incorrect because VPC Flow Logs capture network-level metadata and will only show CloudFront IP addresses, not the original client IPs. Option C is incorrect because disabling connection reuse does not change how client IPs are logged in AWS WAF. Option D is unnecessary and unsupported as a requirement because CloudFront already provides the required information through standard headers.

AWS documentation consistently states thatX-Forwarded-Foris the correct and supported mechanism for tracing client IPs in CloudFront-protected applications.

AWS Certified Security – Specialty Official Study Guide

AWS WAF Developer Guide – Logging

Amazon CloudFront Developer Guide – Request Headers