Secure AWS Access with SAML SSO and IAM Identity Center

Managing access across AWS accounts becomes increasingly complex as organizations grow. Manual credential management doesn’t scale, and traditional IAM users can pose security risks. A better solution is to connect your corporate identity provider to AWS using SAML-based Single Sign-On, now managed through AWS IAM Identity Center.

IAM Identity Center lets your users sign in using their existing enterprise credentials. You can assign fine-grained permissions to individuals or groups, and manage access centrally without maintaining AWS-specific passwords.

Why Use SAML SSO with AWS

SAML SSO lets you authenticate users through your existing identity provider. This improves user experience and security. Users log in with familiar credentials and multifactor authentication, while you maintain centralized control over access policies and audit trails.

What You’ll Set Up

• An identity provider (like Okta, Azure AD, or Google Workspace)
  
• A trust relationship between the provider and AWS IAM Identity Center
  
• Permission sets assigned to users or groups
  
• Optional CLI access via SSO login
  

Step 1: Set Up IAM Identity Center

1. Navigate to IAM Identity Center in the AWS console.
   
2. Choose your identity source. If using an external provider, select “External identity provider” and configure SAML metadata.
   
3. Enable the service across your organization, or target specific accounts.
   

Step 2: Configure Your Identity Provider

1. Add a new SAML application.
   
2. Use the metadata file or URL from IAM Identity Center.
   
3. Map attributes like Subject, email, and groups to match AWS requirements.
   
4. Enable signed requests and encrypted assertions for improved security.
   

Step 3: Assign Permission Sets

1. In IAM Identity Center, define permission sets using AWS managed policies or custom IAM policies.
   
2. Assign these sets to groups or users from your identity provider.
   
3. Choose target accounts for each assignment.
   

Step 4: Test and Use SSO Access

Users can now log into the AWS Management Console using the IAM Identity Center user portal. For CLI access, use the AWS CLI v2 command:

aws sso login –profile your-profile-name

This fetches temporary credentials tied to the permission set and lets users interact with AWS securely from the command line.

Security Best Practices

• Enforce multifactor authentication in your identity provider.
  
• Use short-lived, temporary credentials via SSO instead of static keys.
  
• Enable detailed CloudTrail logging for audit visibility.
  
• Regularly review permission sets and access assignments.
  

Summary

Integrating SAML SSO with IAM Identity Center helps teams manage AWS access at scale. It reduces credential sprawl, improves security posture, and streamlines user experience. By shifting to centralized identity management, your infrastructure becomes both more secure and more manageable. Use SAML and IAM Identity Center to build a strong foundation for access control across all your AWS environments.