Pass the Amazon Web Services AWS Certified Specialty SCS-C03 Questions and answers with CertsForce

Comprehensive and Detailed 100to 150 words of Explanation From AWS Certified Security – Specialty topics:

The best process preserves evidence while minimizing manual access. Security group isolation is a standard EC2 containment method, and detaching from Auto Scaling and load balancers prevents replacement or production routing changes during the investigation. Systems Manager Run Command is preferable to SSH or RDP because it executes scripted collection with auditable command history and avoids interactive login activity that can contaminate evidence. EBS snapshots preserve non-volatile disk data for later forensic analysis, and tagging the instance with incident metadata supports traceability and chain-of-custody workflows. Moving an instance between subnets is disruptive and unnecessary. State Manager is intended for ongoing configuration association, not immediate incident-specific forensic collection with the least overhead.

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Amazon Detective is a managed service designed specifically toinvestigate and analyze security findingsby automatically correlating data from Amazon GuardDuty, AWS CloudTrail, and VPC Flow Logs. According to the AWS Certified Security – Specialty Official Study Guide, Detective enables security teams to identifyroot causes, anomalous behavior, and indicators of compromisethrough interactive visualizations.

Amazon Detective allows investigators to pivot directly toIAM roles, users, and resources that are involved in GuardDuty findings. Detective builds behavior graphs and timelines that show API activity, network traffic, and historical context, making it easier to understand how and why a security incident occurred.

Amazon Inspector (Option B) focuses on vulnerability scanning of compute resources and does not investigate IAM behavior. Option C requires manual analysis and lacks native visualization. AWS Security Hub (Option D) aggregates findings but does not perform root-cause investigation or behavioral analysis.

AWS documentation explicitly states thatAmazon Detective is the recommended service for deep-dive investigations following GuardDuty alerts, especially when IAM roles are involved.

AWS Certified Security – Specialty Official Study Guide

Amazon Detective User Guide

Amazon GuardDuty Integration Documentation

The requirement is to havekey material generated and used inside a custom key store backed by an AWS CloudHSM cluster. This is exactly whatAWS KMS Custom Key Storesprovide: KMS manages the keys and policies, but the cryptographic operations for those KMS keys occur in the associatedCloudHSMcluster, keeping the key material within HSM boundaries. For applications that needlocal-use data keys(both symmetric data keys and asymmetric data key pairs), KMS supports generating data keys and data key pairs that applications can use for envelope encryption and local cryptographic operations, while the master key protections remain within KMS (and within CloudHSM when using a custom key store).

For auditing, AWS best practice isAWS CloudTrail, which records KMS API calls (such as CreateKey, GenerateDataKey, GenerateDataKeyPair, Encrypt/Decrypt, etc.) and provides an immutable event history for compliance and investigation. Athena can query logs, but it is not the primary audit record source; GuardDuty is for threat detection, not authoritative key-usage auditing. Therefore, the correct combination isKMS with a CloudHSM-backed custom key storeplusCloudTrailfor auditability.

Comprehensive and Detailed 100to 150 words of Explanation From AWS Certified Security – Specialty topics:

An S3 gateway endpoint works through route tables. When the gateway endpoint is associated with a subnet route table, AWS automatically adds a route for the S3 prefix list that targets the gateway endpoint. Traffic from resources in that subnet to S3 then uses the private endpoint route instead of the default route through the NAT gateway. Removing the NAT route would disrupt other internet-bound workloads in the subnet and is unnecessary. Gateway endpoint policies control authorization, not route selection. Lambda security group rules do not force S3 traffic to use the gateway endpoint. The missing configuration is associating the S3 gateway endpoint with the route table used by the Lambda function’s subnet.

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AWS incident response best practices emphasizerapid containment with minimal blast radius. According to the AWS Certified Security – Specialty Official Study Guide, isolating a compromised resource while allowing the application to continue running is the preferred initial response.

By using Amazon EventBridge to detect GuardDuty findings related to anomalous traffic and invoking a Lambda function, the security engineer can automatically remove the affected EC2 instance from the Auto Scaling group and attach arestricted security group. This immediately isolates the instance while allowing Auto Scaling to launch a replacement instance, ensuring application availability.

Option A is invalid because EC2 instance profiles do not use long-term access keys. Option C affects the entire subnet and could disrupt unrelated workloads. Option D provides notification only and does not meet the requirement for automated response.

AWS documentation explicitly recommendsinstance-level isolation using security groupsas a best practice for initial incident containment.

AWS Certified Security – Specialty Official Study Guide

Amazon GuardDuty User Guide

AWS Incident Response Best Practices

This is a classic Layer 7 rate-limiting requirement tied toclient IPand atime window, and AWS WAF provides this natively withrate-based rules. Placing AWS WAF in front of the ALB allows the company to count requests per source IP over a rolling window and take action (block, CAPTCHA/challenge, or count depending on configuration) once the threshold is exceeded. This approach mitigates scanning and application-layer request floods early, before requests consume EC2 or DynamoDB capacity, and it requires minimal custom code or operational work.

Options B and C require building and maintaining custom counting logic (either in Lambda or in the application), which increases complexity and risk of errors, and it also introduces operational overhead for scaling state tracking across many IPs. Option D is not appropriate: altering DynamoDB capacity does not enforce “per-IP reads,” and storing per-request metadata in the same table is an anti-pattern that increases write load and complexity.

Therefore, using AWS WAF rate-based protection at the ALB is the least-effort, most effective solution.

KMS grantsare purpose-built for givingtemporary, scoped permissionsto use a customer managed key without continually editing key policies. A grant can allow only the specific cryptographic operations the application process needs (for example, Encrypt/Decrypt/GenerateDataKey) and can be constrained to a particular AWS principal and (optionally) conditions. When access is no longer required, the security team canrevokethe grant immediately, returning the key to its previous access posture. This meets the “temporary access occasionally” requirement with minimal operational work and lower risk than policy churn.

Option B requires repeated key policy edits and rollbacks, which is operationally noisy and increases the chance of misconfiguration or leaving access in place longer than intended. Option A is not supported in the way described—KMS key material for standard KMS customer managed keys is not something you “export” for sharing, and exposing key material breaks managed key controls. Option D introduces significant overhead and complexity by generating/importing key material repeatedly and is not the intended model for occasional access. Grants are the standard AWS pattern for delegating KMS key usage temporarily and safely.

GuardDuty supports “Trusted IP lists” to suppress findings that would otherwise be generated for activity originating from known safe IP addresses (for example, corporate NAT egress IPs, security scanners, or monitoring systems). To use a trusted IP list, you create aplain textfile that contains the IP addresses (typically one per line or in supported list form) and store it inAmazon S3. You then configure GuardDuty to reference that S3 object as a trusted IP list. GuardDuty periodically retrieves the file from S3 and uses it to adjust finding generation accordingly.

That maps directly to Option A (create a plaintext file) and Option D (upload to S3 and create a trusted IP list in GuardDuty pointing to the file).

Options B and E are incorrect because GuardDuty trusted IP lists are not configured by pasting JSON into the console; they are sourced from an S3-hosted text list. Option C is not supported because GuardDuty does not accept direct file uploads into the service as the configuration source; S3 is the expected integration point for IP lists and threat intel lists.

AWS Systems Manager Run Command enables secure, remote execution of commands on EC2 instances without requiring network access or inbound ports. According to the AWS Certified Security – Specialty Study Guide, Run Command is a recommended mechanism for incident response actions such as installing forensic tools, collecting evidence, or applying quarantine controls.

By granting the SSM Agent permission to execute a predefined Run Command document, the security engineer can immediately run the quarantine script across affected instances. This approach supports automation, scalability, and auditability, all of which are critical during security incidents.

Options A, B, and C do not directly enforce quarantine or execute response actions. Tracking versions and storing scripts alone do not trigger incident response.

AWS documentation highlights Systems Manager Run Command as a core capability for automated containment and investigation.

Referenced AWS Specialty Documents:

AWS Certified Security – Specialty Official Study Guide

AWS Systems Manager Run Command

AWS Incident Response Automation

Comprehensive and Detailed 100to 150 words of Explanation From AWS Certified Security – Specialty topics:

AWS WAF protects HTTP and HTTPS application traffic by inspecting requests and applying rules such as SQL injection match statements. AWS WAF can be associated with supported resources, including Application Load Balancers, but it cannot be attached directly to EC2 instances. Creating an ALB with the existing EC2 instances as targets preserves normal application operation while allowing the web ACL to inspect and block malicious SQL injection patterns. After testing, Route 53 can be redirected to the ALB, and EC2 security groups should be restricted so users cannot bypass WAF by reaching the instances directly. Patching unsupported legacy software within 24 hours is higher effort and riskier. CloudFront with only one EC2 origin would not preserve the current two-instance weighted design.

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