SCS-C02 Amazon Web Services AWS Certified Security - Specialty Free Practice Exam Questions (2025 Updated)

The correct answer is A. Revoke all versions of the signing profile assigned to the developer.

According to the AWS documentation1, AWS Signer is a fully managed code-signing service that helps you ensure the trust and integrity of your code. You can use Signer to sign code artifacts, such as Lambda deployment packages, with code-signing certificates that you control and manage.

A signing profile is a collection of settings that Signer uses to sign your code artifacts. A signing profile includes information such as the following:

The type of signature that you want to create (for example, a code-signing signature).

The signing algorithm that you want Signer to use to sign your code.

The code-signing certificate and its private key that you want Signer to use to sign your code.

You can create multiple versions of a signing profile, each with a different code-signing certificate. You can also revoke a version of a signing profile if you no longer want to use it for signing code artifacts.

In this case, the company wants to ensure that all the code that the developer wrote can no longer be deployed to the Lambda functions. One way to achieve this is to revoke all versions of the signing profile that was assigned to the developer. This will prevent Signer from using that signing profile to sign any new code artifacts, and also invalidate any existing signatures that were created with that signing profile. This way, the company can ensure that only trusted and authorized code can be deployed to the Lambda functions.

The other options are incorrect because:

B. Examining the developer’s IAM roles and removing all permissions that grant access to Signer may not be sufficient to prevent the deployment of the developer’s code. The developer may have already signed some code artifacts with a valid signing profile before leaving the company, and those signatures may still be accepted by Lambda unless the signing profile is revoked.

C. Re-encrypting all source code with a new AWS Key Management Service (AWS KMS) key may not be effective or practical. AWS KMS is a service that lets you create and manage encryption keys for your data. However, Lambda does not require encryption keys for deploying code artifacts, only valid signatures from Signer. Therefore, re-encrypting the source code may not prevent the deployment of the developer’s code if it has already been signed with a valid signing profile. Moreover, re-encrypting all source code may be time-consuming and disruptive for other developers who are working on the same code base.

D. Using Amazon CodeGuru to profile all the code that the Lambda functions use may not help with preventing the deployment of the developer’s code. Amazon CodeGuru is a service that provides intelligent recommendations to improve your code quality and identify an application’s most expensive lines of code. However, CodeGuru does not perform any security checks or validations on your code artifacts, nor does it interact with Signer or Lambda in any way. Therefore, using CodeGuru may not prevent unauthorized or untrusted code from being deployed to the Lambda functions.

To allow cross-account access to resources using IAM roles, the following steps are required:

Create a role in the AWS account that contains the resources (the trusting account) and specify the AWS account that contains the IAM user (the trusted account) as a trusted entity in the role’s trust policy. This allows users from the trusted account to assume the role and access resources in the trusting account.

Ensure that the IAM user has permission to assume the role in their own AWS account. This can be done by creating an identity policy that allows the sts:AssumeRole action and attaching it to the IAM user or their group.

Ensure that there are no service control policies (SCPs) in the organization that owns the resources that deny or restrict access to the sts:AssumeRole action or the role itself. SCPs are applied to all accounts in an organization and can override any permissions granted by IAM policies.

Verified References:

https://repost.aws/knowledge-center/cross-account-access-iam

https://docs.aws.amazon.com/organizations/latest/userguide/orgs_manage_accounts_access.html

https://docs.aws.amazon.com/IAM/latest/UserGuide/tutorial_cross-account-with-roles.html

Understand the Issue:

KMS grants are created using theCreateGrantoperation.

The grant might not propagate immediately for use, leading toAccessDeniedExceptionerrors.

Use Grant Tokens for Immediate Access:

When a grant is created, AWS KMS provides a grant token in the response.

This grant token can be used immediately, even before the grant is fully propagated.

Implement Solution:

Pass the grant token returned byCreateGrantto the users.

Ensure users include the grant token in their requests to encrypt data.

AWS KMS Grant Tokens Documentation

Troubleshooting KMS AccessDenied Errors

The correct answer is B. Instruct users to run the aws sts get-session-token CLI command and pass the multi-factor authentication --serial-number and --token-code parameters. Use these resulting values to make API/CLI calls.

According to the AWS documentation1, the aws sts get-session-token CLI command returns a set of temporary credentials for an AWS account or IAM user. The credentials consist of an access key ID, a secret access key, and a security token. These credentials are valid for the specified duration only. The session duration for IAM users can be between 15 minutes and 36 hours, with a default of 12 hours.

You can use the --serial-number and --token-code parameters to provide the MFA device serial number and the MFA code from the device. The MFA device must be associated with the user who is making the get-session-token call. If you do not provide these parameters when your IAM user or role has a policy that requires MFA, you will receive an Access Denied error.

The temporary security credentials that are returned by the get-session-token command can then be used to make subsequent API or CLI calls that require MFA authentication. You can use environment variables or a profile in your AWS CLI configuration file to specify the temporary credentials.

Therefore, this solution will resolve the problem of users being unable to perform EC2 commands using the AWS CLI, while still enforcing MFA.

The other options are incorrect because:

A. Changing the value of aws:MultiFactorAuthPresent to true will not work, because this is a condition key that is evaluated by AWS when a request is made. You cannot set this value manually in your policy or request. You must provide valid MFA information to AWS for this condition key to be true.

C. Implementing federated API/CLI access using SAML 2.0 may work, but it requires more operational effort than using the get-session-token command. You would need to configure a SAML identity provider and trust relationship with AWS, and use a custom SAML client to request temporary credentials from AWS STS. This solution may also introduce additional security risks if the identity provider is compromised.

D. Creating a role and enforcing MFA in the role trust policy may work, but it also requires more operational effort than using the get-session-token command. You would need to create a role for each user or group that needs to perform EC2 commands, and specify a trust policy that requires MFA. You would also need to grant the users permission to assume the role, and instruct them to use the sts assume-role command instead of the get-session-token command.

Option A: This option meets the requirements of following security best practices and configuring sensitive database credentials in the CloudFormation template. A dynamic reference is a way to specify external values that are stored and managed in other services,such as Secrets Manager, in the stack templates1. When using a dynamic reference, CloudFormation retrieves the value of the specified reference when necessary during stack and change set operations1. Dynamic references can be used for certain resources that support them, such as AWS::RDS::DBInstance1. By using a dynamic reference to reference the database credentials in Secrets Manager, the company can leverage the existing integration between these services and avoid hardcoding the secret information in the template. Secrets Manager is a service that helps you protect secrets needed to access your applications, services, and IT resources2. Secrets Manager enables you to rotate, manage,and retrieve database credentials, API keys, and other secrets throughout theirlifecycle2.

Establishing a VPC peering connection between the VPCs in Account A and Account B and updating route tables, network ACLs, and security groups to permit the necessary traffic ensures private connectivity for the application to write to the S3 bucket without traversing the public internet. This solution is efficient and maintains network security and integrity.

Verify File Permissions:

Ensure that the log files being monitored by the CloudWatch Logs agent are still accessible.

Check permissions to confirm that the agent's process can read the files.

Check Log Rotation Rules:

Operating systems may rotate logs periodically, causing the monitored file path to change.

Update the CloudWatch Logs agent configuration to handle rotated log files (e.g., wildcards or new file paths).

Diagnose with Agent Logs:

Review the agent logs in/var/log/amazon/or equivalent to identify potential issues.

Amazon CloudWatch Logs Agent Setup

Handling Log Rotation

The correct answer is A because it allows the security engineer to add the X-Frame-Options header to the HTTPS responses from the application origin without modifying the origin itself. A Lambda@Edge function is a Lambda function that runs in response to CloudFront events, such as viewer request, origin request, origin response, or viewer response. By configuring the function to runin response to the origin response event, the security engineer can modify the response headers that CloudFront receives from the origin before sending them to the viewer1. The function can include code to add the X-Frame-Options header with the desired value, suchas DENY or SAMEORIGIN, to prevent frame-related cross-site scripting attacks2.

The other options are incorrect because they are either less efficient or less secure than option A. Option B is incorrect because configuring the Lambda@Edge function to run in response to the viewer request event is not optimal, as it adds latency to the request processing and does not modify the response headers that CloudFront receives from the origin. Option C is incorrect because adding X-Frame-Options to custom headers in the origin settings does not affect the response headers that CloudFront sends to the viewer. Custom headers are only used to send additional information to the origin when CloudFront forwards a request3. Option D is incorrect because customizing the EC2 hosted application to add the X-Frame-Options header to the responses requires changing the origin code, which may not be feasible or desirable for the security engineer.

This solution meets the requirement of recovering the EC2 instances if the AWS account is compromised and the EBS snapshots are deleted. By creating a new AWS account with limited privileges, the company can isolate the backup snapshots from the main account and reduce the risk of accidental or malicious deletion. By allowing the new account to access the KMS key that encrypts the EBS snapshots, the company can ensure that the snapshots are copied in an encrypted form and can be decrypted when needed. By copying the encrypted snapshots to the new account on a recurring basis, the company can maintain a consistent backup schedule and minimize data loss.

Open the AWS Systems Manager console at https://console.aws.amazon.com/systems-manager/. In the navigation pane, choose Session Manager. Choose the Preferences tab, and then choose Edit. Select the check box next to Enable under S3 logging. (Recommended) Select the check box next to Allow only encrypted S3 buckets. With this option turned on, log data is encrypted using the server-side encryption key specified for the bucket. If you don 't want to encrypt the log data that is sent to Amazon S3, clear the check box. You must also clear the check box if encryption isn't allowed on the S3 bucket.

To troubleshoot the issue of an EC2 instance failing to start and transitioning to a terminated state when it has an EBS volume encrypted with an AWS KMS customer managed key, a security engineer should take the following steps:

C. Verify that the KMS key that is associated with the EBS volume is in the Enabled state. If the key is not enabled, it will not function properly and could cause the EC2 instance to fail.

D. Verify that the EC2 role that is associated with the instance profile has the correct IAM instance policy to launch an EC2 instance with the EBS volume. If the instance does not have the necessary permissions, it may not be able to mount the volume and could cause the instance to fail.

Therefore, options C and D are the correct answers.

Enable GuardDuty:

GuardDuty provides monitoring for EKS clusters by analyzing EKS audit logs.

Automatic Configuration:

No additional setup for the EKS deployment is needed. GuardDuty directly monitors API calls to detect suspicious or unauthenticated access.

Advantages:

Minimal Effort: No operational overhead for configuration.

Proactive Detection: Alerts for unauthorized or suspicious activity in near-real-time.

Amazon GuardDuty for EKS

EKS Audit Log Monitoring