2.2.1. Auditing IAM (Access Analyzer, Credential Report)

First Principle: Auditing IAM access (e.g., with Access Analyzer and Credential Report) fundamentally provides transparency into permissions, identifies potential risks, and helps ensure adherence to the Principle of Least Privilege.

Regularly auditing IAM configurations is critical for maintaining a strong security posture. It helps identify overly permissive policies, unused credentials, and unintended public access.

Key Tools for Auditing IAM Access:

• IAM Access Analyzer:
  • What it is: A service that helps you identify the resources in your organization and accounts that are shared with an external entity. It continuously monitors access to resources (e.g., S3 buckets, KMS keys, SQS queues, IAM roles) and identifies potential unintended public or cross-account access.
  • Benefits: Proactively identifies security risks from external access.
• IAM Credential Report:
  • What it is: A report that lists all users in your account and the status of their various credentials (e.g., password last used, access key last used, MFA enabled).
  • Benefits: Helps identify unused credentials, credentials that haven't been rotated, or users without MFA enabled.
• IAM Policy Simulator: Allows you to test and troubleshoot IAM policies. Helps verify effective permissions for a specific IAM identity and action.
• AWS CloudTrail: Records API calls and resource changes. Provides an audit trail for all IAM actions.

Scenario: You need to perform a security audit of your AWS account. You're particularly concerned about any S3 buckets that might be unintentionally public and identify any IAM users with unused or long-lived credentials.

Reflection Question: How does auditing IAM access using tools like IAM Access Analyzer (for external access) and the Credential Report (for credential status) fundamentally provide transparency into permissions, identify potential risks, and help ensure adherence to the Principle of Least Privilege?