Securing EC2 Instances and S3 Bucket Access

Answer - B and D.

The AWS Documentation mentions the following.

IAM roles are designed so that your applications can securely make API requests from your instances, without requiring you to manage the security credentials that the applications use.

Instead of creating and distributing your AWS credentials, you can delegate permission to make API requests using IAM roles

For more information on IAM Roles, please refer to the below link:

http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/iam-roles-for-amazon-ec2.html

MFA Delete can be used to add another layer of security to S3 Objects to prevent accidental deletion of objects ( it is upto the user to check for accidental deletion of the objects even after implementation of MFA )

For more information on MFA Delete, please refer to the below link:

https://aws.amazon.com/blogs/security/securing-access-to-aws-using-mfa-part-3/

The architecture in question has EC2 Instances that access data objects stored in an S3 bucket. The IT Security department is concerned about the security of this architecture and wants you to implement a solution to enhance the security of the system.

Option A suggests creating an IAM user and ensuring that the EC2 Instances use the IAM user credentials to access the data in the bucket. IAM users are entities that can represent a person, application, or service that needs access to AWS resources. The user credentials include a user name and password, which are used to authenticate and authorize access to AWS resources. This option may be a valid solution if the EC2 Instances are running a specific application or service that requires AWS access, and it's necessary to restrict access to specific users. However, managing IAM users can be a burden on the IT team and can be time-consuming. Furthermore, the use of IAM users introduces the risk of compromised credentials, which can lead to security breaches.

Option B suggests creating an IAM Role and ensuring that the EC2 Instances use the IAM Role to access the data in the bucket. An IAM role is an AWS identity with permission policies that determine what the identity can and cannot do in AWS. Roles can be assumed by AWS services, applications, or users that have been authenticated outside of AWS. By using an IAM role, the EC2 Instances can assume the role when they need access to AWS resources, and the security credentials will be provided by AWS, eliminating the need for long-term security credentials. This approach provides a more secure way of granting access to AWS resources, and it reduces the risk of compromised credentials. This option is a better solution than Option A.

Option C suggests using S3 Cross Region replication to replicate the objects, ensuring the integrity of the data is maintained. S3 Cross Region replication is a feature that automatically replicates objects from a source bucket to a destination bucket in a different AWS region. This feature is useful for disaster recovery, compliance, and data locality. However, it does not address the security concerns of the IT Security department, and it does not prevent unauthorized access to the data in the bucket.

Option D suggests enabling versioning on the objects and ensuring that MFA Delete is set on the objects in the bucket. Versioning is a feature that allows you to preserve, retrieve, and restore every version of every object in an S3 bucket. MFA Delete is an S3 bucket feature that adds an extra layer of protection to prevent the accidental deletion of objects by requiring MFA authentication. This option is a valid solution for enhancing the security of the S3 bucket. By enabling versioning, you can track changes made to the objects, and by enabling MFA Delete, you can prevent accidental or malicious deletion of objects.

In conclusion, Option B (creating an IAM Role and ensuring the EC2 Instances use the IAM Role to access the data in the bucket) and Option D (enabling versioning on the objects and ensuring that MFA Delete is set on the objects in the bucket) are the best solutions to address the security concerns of the IT Security department.