AWS IAM Security

What is AWS IAM?

AWS Identity and Access Management (IAM) is a security framework that governs who can access AWS resources and what actions they can perform. It functions as a digital bouncer, ensuring only authorized users and applications interact with AWS services.

Unlike traditional access control systems, IAM operates on a zero-trust model, where every request is evaluated against explicit permissions. It allows fine-grained control through policies, roles, and temporary credentials, ensuring secure and scalable access management.

IAM is not just about users—it also manages access for AWS services, external identity providers, and applications, making it a central pillar of AWS security architecture.

Unique Features of AWS IAM

• No Passwords for Services – AWS services don’t need passwords; they use IAM roles to securely interact with other services.
• Temporary Access Instead of Static Keys – IAM roles provide temporary credentials, reducing the risk of leaked long-term access keys.
• Permissions Boundaries – Even administrators can have limits on what permissions they can grant to others, preventing privilege escalation.
• Cross-Account Access Without Sharing Credentials – You can grant access to users from another AWS account securely without sharing usernames or passwords.
• Condition-Based Access – IAM policies can restrict access based on factors like IP address, time of day, or whether MFA is enabled.
• Automated Security Analysis – IAM Access Analyzer helps detect overly permissive policies that might expose resources unintentionally.

How IAM Works?

• Identities : IAM provides identities in the form of users, groups, and roles.
• Authentication : Users authenticate using passwords, access keys, or federated identities (e.g., SSO).
• Authorization : IAM policies define permissions that allow or deny actions on AWS resources.
• Roles and Temporary Credentials : IAM roles grant permissions to services and users without needing long-term credentials.

IAM Components

• Users : Individuals with AWS accounts who need specific permissions.
• Groups : A collection of users sharing common permissions.
• Roles : Used to grant access to AWS services or external entities.
• Policies : JSON-based documents defining permissions for users, groups, and roles.
• Identity Federation : Allows users to access AWS resources using existing corporate credentials.
• MFA (Multi-Factor Authentication) : Adds an extra layer of security by requiring additional authentication factors.

Best Practices

• Least Privilege Principle : Grant only necessary permissions.
• Use IAM Roles Instead of Access Keys : Avoid long-term credentials.
• Enable MFA : Protect critical accounts.
• Regularly Rotate Credentials : Reduce risk exposure.
• Monitor IAM Activities : Use AWS CloudTrail for auditing.

How IAM Protects AWS Resources?

• IAM policies are attached to users, groups, or roles to specify what actions they can perform.
• Resource-based policies (like S3 bucket policies) control access at the resource level.
• Service control policies (SCPs) manage permissions across AWS Organizations.
• Session policies apply temporary permissions for IAM roles and federated users.