Pass the Amazon Web Services AWS Certified Specialty SCS-C02 Questions and answers with ValidTests

To set up a CloudFront distribution for an S3 bucket that hosts a static website, and to allow only specified IP addresses to access the website, the following steps are required:

Create a CloudFront origin access identity (OAI), which is a special CloudFront user that you can associate with your distribution. An OAI allows you to restrict access to your S3 content by using signed URLs or signed cookies. For more information, see Using an origin access identity to restrict access to your Amazon S3 content.

Create the S3 bucket policy so that only the OAI has access. This will prevent users from accessing the website directly by using S3 URLs, as they will receive an Access Denied error. To do this, use the AWS Policy Generator to create a bucket policy that grants s3:GetObject permission to the OAI, and attach it to the S3 bucket. For more information, see Restricting access to Amazon S3 content by using an origin access identity.

Create an AWS WAF web ACL and add an IP set rule. AWS WAF is a web application firewall service that lets you control access to your web applications. An IP set is a condition that specifies a list of IP addresses or IP address ranges that requests originate from. You can use an IP set rule to allow or block requests based on the IP addresses of the requesters.For more information, see Working with IP match conditions.

Associate the web ACL with the CloudFront distribution. This will ensure that the web ACL filters all requests for your website before they reach your origin. You can do this by using the AWS WAF console, API, or CLI. For more information, see Associating or disassociating a web ACL with a CloudFront distribution.

This solution will meet the requirements of allowing only specified IP addresses to access the website and preventing direct access by using S3 URLs.

The other options are incorrect because they either do not create a CloudFront distribution for the S3 bucket (A), do not use an OAI to restrict access to the S3 bucket ©, or do not use AWS WAF to block traffic from outside the specified IP addresses (D).

Verified References:

https://docs.aws.amazon.com/AmazonCloudFront/latest/DeveloperGuide/private-content-restricting-access-to-s3.html

https://docs.aws.amazon.com/waf/latest/developerguide/web-acl-ip-conditions.html

The correct answer is A. Use IAM Access Analyzer policy generation to generate a policy that allows the CloudFormation script to run and manage the stack. Attach the policy to a new IAM role. Modify the security engineer’s IAM permissions to be able to pass the new role to CloudFormation.

According to the AWS documentation, IAM Access Analyzer is a service that helps you identify the resources in your organization and accounts, such as Amazon S3 buckets or IAM roles, that are shared with an external entity. You can also use IAM Access Analyzer to generate fine-grained policies that grant least privilege access based on access activity and access attempts.

To use IAM Access Analyzer policy generation, you need to enable IAM Access Analyzer in your account or organization. You can then use the IAM console or the AWSCLI to generate a policy for a resource based on its access activity or access attempts. You can review and edit the generated policy before applying it to the resource.

To use IAM Access Analyzer policy generation with CloudFormation, you can follow these steps:

Run the CloudFormation script in a pre-production environment and monitor its access activity or access attempts using IAM Access Analyzer.

Use IAM Access Analyzer policy generation to generate a policy that allows the CloudFormation script to run and manage the stack. The policy will include only the permissions that are necessary for the script to function.

Attach the policy to a new IAM role that has a trust relationship with CloudFormation. This will allow CloudFormation to assume the role and execute the script.

Modify the security engineer’s IAM permissions to be able to pass the new role to CloudFormation. This will allow the security engineer to launch the stack using the role.

Run the CloudFormation script in the production environment using the new role.

This solution will meet the requirements of least privilege and separation of duties, as it will limit the permissions of both CloudFormation and the security engineer to only what is needed for running and managing the stack.

Option B is incorrect because creating an IAM policy that allows ec2:* and rds:* permissions is not following the principle of least privilege, as it will grant more permissions than necessary for running and managing the stack. Moreover, modifying the security engineer’s IAM permissions to be able to assume the new role is not ensuring separation of duties, as it will allow the security engineer to bypass CloudFormation and directly access the resources.

Option C is incorrect because modifying the security engineer’s IAM permissions to be able to run the CloudFormation script is not ensuring separation of duties, as it will allow the security engineer to execute the script without using CloudFormation.

Option D is incorrect because creating an IAM policy that allows ec2:* and rds:* permissions is not following the principle of least privilege, as it will grant more permissions than necessary for running and managing the stack. Using the IAM policy simulator to confirm that the policy allows the AWS API calls that are necessary to build the stack is not sufficient, as it will not generate a fine-grained policy based on access activity or access attempts.

https://docs.aws.amazon.com/organizations/latest/userguide/orgs_manage_policies_scps_syntax.html#scp-elements-table

The correct answer is C. Update the existing bucket policy in the Amazon S3 console with the new log file prefix, and then update the log file prefix in the CloudTrail console.

According to the AWS documentation1, a bucket policy is a resource-based policy that you can use to grant access permissions to your Amazon S3 bucket and the objects in it. Only the bucket owner can associate a policy with a bucket. The permissions attached to the bucket apply to all of the objects in the bucket that are owned by the bucket owner.

When you create a trail in CloudTrail, you can specify an existing S3 bucket or create a new one to store your log files. CloudTrail automatically creates a bucket policy for your S3 bucket that grants CloudTrail write-only access to deliver log files to your bucket. The bucket policy also grants read-only access to AWS services that you can use to view and analyze your log data, such as Amazon Athena, Amazon CloudWatch Logs, and Amazon QuickSight.

If you want to update the log file prefix for an existing trail, you must also update the existing bucket policy in the S3 console with the new log file prefix. The log file prefix is part of the resource ARN that identifies the objects in your bucket that CloudTrail canaccess. If you don’t update the bucket policy with the new log file prefix, CloudTrail will not be able to deliver log files to your bucket, and you will receive an error message when you try to save the change in the CloudTrail console.

The other options are incorrect because:

A. Creating a new trail with the updated log file prefix, and then deleting the original trail is not necessary and may cause data loss or inconsistency. You can simply update the existing trail and its associated bucket policy with the new log file prefix.

B. Updating the existing bucket policy in the S3 console to allow the Security Engineer’s Principal to perform PutBucketPolicy is not relevant to this issue. The PutBucketPolicy action allows you to create or replace a policy on a bucket, but it does not affect CloudTrail’s ability to deliver log files to your bucket. You still need to update the existing bucket policy with the new log file prefix.

D. Updating the existing bucket policy in the S3 console to allow the Security Engineer’s Principal to perform GetBucketPolicy is not relevant to this issue. The GetBucketPolicy action allows you to retrieve a policy on a bucket, but it does not affect CloudTrail’s ability to deliver log files to your bucket. You still need to update the existing bucket policy with the new log file prefix.

Amazon EC2 Systems Manager is a service that helps you automatically collect software inventory, apply OS patches, create system images, and configure Windows and Linux operating systems3. You can use Systems Manager to report on instance patch compliance and enforce updates during the defined maintenance windows4. The other options are either inefficient or not feasible for achieving the goals.

https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-eni.html#eni-basics Source/destination checking "You must disable source/destination checks if the instance runs services such as network address translation, routing, or firewalls."

The correct answer is C. Disable the Network Source/Destination check on the security appliance’s elastic network interface.

This answer is correct because disabling the Network Source/Destination check allows the virtual security appliance to route traffic that is not addressed to or from itself. By default, this check is enabled on all EC2 instances, and it prevents them from forwarding traffic that does not match their own IP or MAC addresses.However, for a virtual security appliance that acts as a router or a firewall, this check needs to be disabled, otherwise it will drop the traffic that it is supposed to route12.

The other options are incorrect because:

A. Disabling network ACLs is not a solution, because network ACLs are optional layers of security for the subnets in a VPC.They can be used to allow or deny traffic based on IP addresses and ports, but they donot affect the routing behavior of the virtual security appliance3.

B. Configuring the security appliance’s elastic network interface for promiscuous mode is not a solution, because promiscuous mode is a mode for a network interface that causes it to pass all traffic it receives to the CPU, rather than passing only the frames that it is programmed to receive.Promiscuous mode is normally used for packet sniffing or monitoring, but it does not enable the network interface to route traffic4.

D. Placing the security appliance in the public subnet with the internet gateway is not a solution, because it does not address the routing issue of the virtual security appliance.Thesecurity appliance can be placed in either a public or a private subnet, depending on the network design and security requirements, but it still needs to have the Network Source/Destination check disabled to route traffic properly5.