Restrict Root User Capabilities Using Service Control Policies (SCPs):

SCPs in AWS Organizations provide the ability to control permissions for AWS accounts in the organization.

Create a new organizational unit (OU) and move all member accounts into this OU.

Create SCP for Root User Restrictions:

Define an SCP that denies critical actions likeiam:CreateUser,iam:DeleteUser, or other high-risk actions for the root user. Example SCP:

{

"Version": "2012-10-17",

"Statement": [

{

"Effect": "Deny",

"Action": "*",

"Resource": "*",

"Condition": {

"StringEquals": {

"aws:PrincipalAccountRoot": "true"

}

}

}

]

}

Enforce Multi-Factor Authentication (MFA):

Enable MFA on root accounts for additional security.

Monitor Root User Activity:

Use AWS CloudTrail to monitor and log root user actions. Configure alerts with CloudWatch for any unauthorized root usage.

AWS Organizations SCP Documentation

Best Practices for Root User Account