All checks
Medium
EC2 subnets should not automatically assign public IP addresses
Flags EC2 subnets configured to automatically assign public IPv4 addresses or IPv6 addresses to instances at launch, which gives new instances there a publicly routable address by default, whether or not they need one. The setting applies only at launch.
- service
- EC2
- severity
- Medium
- scope
- evaluated in every region
How to fix it
In the console
VPC → Subnets → the subnet → Actions → Edit subnet settings → Auto-assign IP settings
With the AWS CLI
aws ec2 modify-subnet-attribute --subnet-id <subnet-id> --no-map-public-ip-on-launch --region <region>With Terraform
resource "aws_subnet" "this" {
vpc_id = var.vpc_id
cidr_block = var.cidr_block
map_public_ip_on_launch = false
assign_ipv6_address_on_creation = false
}See which of your accounts this check is failing on.
Book a demo