What is a recommended IAM best practice?

Employing the principle of least privilege is recognized as a fundamental best practice within IAM (Identity and Access Management) in AWS. This principle dictates that users, applications, and services should only be granted the permissions they absolutely need to perform their tasks, and nothing more. By limiting permissions, you reduce the potential attack surface that could be exploited by malicious actors or inadvertently mishandled by users.

For example, if a user only needs to read data from a specific S3 bucket, they should not be granted permissions to delete objects or list all buckets in your account. This approach not only enhances security by minimizing exposure but also aids in compliance with regulatory requirements that may mandate strict access controls.

In contrast, options such as enabling automatic billing for all services, using a single IAM user for all operations, and disabling Multi-Factor Authentication do not align with the best practices for secure IAM management. Enabling automatic billing does not relate to user access controls, while using a single IAM user for all operations compromises accountability and audit capabilities. Disabling Multi-Factor Authentication (MFA) reduces security by removing an additional layer of protection that helps prevent unauthorized access. Thus, the principle of least privilege stands out as the most important practice in managing permissions effectively and