Which solution will meet these requirements in the MOST secure way?
Create an IAM role that has permissions to access the database. Attach the IAM role to the EC2 instances.
Store the credentials as secrets in AWS Secrets Manager. Create an AWS Lambda function to update the secrets and the database. Retrieve the credentials from Secrets Manager as needed.
Store the credentials in an encrypted text file in an Amazon S3 bucket. Configure the EC2 instance launch template to download the credentials from Amazon S3 as the instance launches. Create an AWS Lambda function to update the secrets and the database.
Store the credentials in an Amazon DynamoDB table. Configure an Amazon CloudWatch Events rule to invoke an AWS Lambda function to periodically update the secrets and database.
Explanations:
While creating an IAM role for EC2 instances is a good practice for granting permissions, IAM roles cannot directly manage database credentials or automate rotation. This option does not fulfill the requirement of securely storing and automatically rotating database credentials.
AWS Secrets Manager is specifically designed for securely storing, managing, and automatically rotating credentials. Using Secrets Manager allows the application to retrieve database credentials programmatically without hardcoding them in the code. This meets both the security and automation requirements effectively.
Storing credentials in an encrypted text file in S3 is less secure than using a dedicated secrets management service. Although S3 can be used to store files securely, it lacks built-in credential rotation features and poses risks if the S3 bucket is not properly secured or if the access is misconfigured.
Storing credentials in DynamoDB does not provide the same level of security and automation as Secrets Manager. Although Lambda can be used to update the database credentials, this option lacks the built-in functionality for secure storage and automatic rotation that Secrets Manager offers, making it less secure overall.
I systematize that the answer is:
Store the credentials as secrets in AWS Secrets Manager. Create an AWS Lambda function to update the secrets and the database. Retrieve the credentials from Secrets Manager as needed.