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.

what the Security Engineer should do to block the malicious bot. SFTP is a protocol that allows secure file transfer over SSH. EC2 is a service that provides virtual servers in the cloud. A public subnet is a subnet that has a route to an internet gateway, which allows it to communicate with the internet. A brute force attack is a type of attack that tries to guess passwords or keys by trying many possible combinations. A malicious bot is a software program that performs automated tasks for malicious purposes. Route 53 is a service that provides DNS resolution and domain name registration. A DNS sinkhole is a technique that redirects malicious or unwanted traffic to a different destination, such as a black hole server or a honeypot. By modifying the hosted zone in Route 53 and creating a DNS sinkhole for the malicious IP, the Security Engineer can block the malicious bot from reaching the EC2 instance on the public subnet. The other options are either ineffective or inappropriate for blocking the malicious bot.

the most secure way to meet the requirements. TLS is a protocol that provides encryption and authentication for data in transit. ALB is a service that distributes incoming traffic across multiple EC2 instances. HIDS is a system that monitors and detects malicious activity on a host. ECDHE is a type of cipher suite that supports perfect forward secrecy, which is a property that ensures that past and current TLS traffic stays secure even if the certificate private key is leaked. By creating a listener on the ALB that does not enable PFS cipher suites, and using encrypted connections to the servers using ECDHE cipher suites, you can ensure that the HIDS agents can capture the traffic of the EC2 instance without compromising the privacy of the users. The other options are either less secure or less compatible with the third-party solution.

To ensure that database credentials are stored securely and rotated periodically, the security engineer should do the following:

Use AWS Secrets Manager to store database credentials. This allows the security engineer to encrypt and manage secrets centrally, and to configure automatic rotation schedules for them.

Use IAM roles for ECS tasks to restrict access to database credentials to specific containers only. This allows the security engineer to grant fine-grained permissions to ECS tasks based on their roles, and to avoid sharing credentials as plaintext with other teammates.

To secure the images to limit their distribution, the company should take the following actions:

Update the S3 bucket policy to restrict access to a CloudFront origin access identity (OAI). This allows the company to use a special CloudFront user that can access objects in their S3 bucket, and prevent anyone else from accessing them directly.

Add a CloudFront geo restriction deny list of countries where the company lacks a license. This allows the company to use a feature that controls access to their content based on the geographic location of their viewers, and block requests from countries where they do not have a distribution license.

The correct answer is A because it meets the RPO of 1 hour by creating backups of the EC2 instances and S3 buckets every hour. It also uses AWS CloudFormation templates to replicate the existing architecture components and AWS CodeCommit to store the templates and the application configuration code. This way, the security engineer can quickly restore the environment in case of a ransomware attack.

The other options are incorrect because they do not meet the RPO of 1 hour or they do not provide a complete disaster recovery solution. Option B only creates backups of the EBS volumes and S3 objects every day, which is not frequent enough to meet the RPO. Option C does not create any backups of the EC2 instances or the S3 buckets, which are essentialfor the frontend services. Option D only creates EBS snapshots every 4 hours, which is also not frequent enough to meet the RPO. Additionally, option D relies on Amazon GuardDuty to detect and respond to ransomware attacks, which may not be effective if the attacker bypasses the preventive and detective controls.

The correct answer is D. Attach the CloudWatchAgentServerPolicy AWS managed policy to the EC2 instance role.

According to the AWS documentation1, the CloudWatch agent is a software agent that you can install on your EC2 instances to collect system-level metrics and logs. To use the CloudWatch agent, you need to attach an IAM role or user to the EC2 instance thatgrants permissions for the agent to perform actions on your behalf.The CloudWatchAgentServerPolicy is an AWS managed policy that provides the necessary permissions for the agent to write metrics and logs to CloudWatch2. By attaching this policy to the EC2 instance role, the security engineer can resolve the issue of CloudWatch not receiving the custom application-security logs.

The other options are incorrect for the following reasons:

A.Adding AWS CloudTrail to the trust policy of the EC2 instance is not relevant, because CloudTrail is a service that records API activity in your AWS account, not custom application logs3. Sending the custom logs to CloudTrail instead of CloudWatch would not meet the requirement of forwarding them to CloudWatch.

B.Adding Amazon S3 to the trust policy of the EC2 instance is not necessary, because S3 is a storage service that does not require any trust relationship with EC2 instances4. Configuring the application to write the custom logs to an S3 bucket that CloudWatch can use to ingest the logs would be an alternative solution, but it would be more complex and costly than using the CloudWatch agent directly.

C.Adding Amazon Inspector to the trust policy of theEC2 instance is not helpful, because Inspector is a service that scans EC2 instances for software vulnerabilities and unintended network exposure, not custom application logs5. Using Amazon Inspector instead of the CloudWatch agent would not meet the requirement of forwarding them to CloudWatch.

Create an Account-Wide Data Protection Policy:

Use AWS CloudWatch Logs account-level data protection policies to prevent sensitive data exposure.

Define the policy with appropriate AWS managed data identifiers or custom identifiers specific to the company's sensitive data.

Apply the policy across all log groups in the account, ensuring coverage for both existing and future log groups.

Restrict Developer Access to Unmasked Data:

Explicitly deny thelogs:UnmaskIAM permission to developers. This prevents developers from accessing unmasked sensitive data in log entries.

Automatic Policy Application:

Account-wide data protection policies automatically apply to new log groups created in the future, ensuring scalability and compliance without manual intervention.

Testing and Verification:

Test the policy with sample log entries containing sensitive data to ensure proper masking.

Verify that developers can troubleshoot logs without exposing sensitive information.

AWS CloudWatch Logs Data Protection Documentation

AWS Identity and Access Management Permissions for CloudWatch Logs