Subnet should not auto-assign public IPs
High
AWS
General
aws-ec2-subnet-subnet-auto-assign-public-ips
Applies to
AWS::EC2::Subnet
What CGPulse checks
A resource passes this rule when mapPublicIpOnLaunch must equal false. Anything else is reported as a finding with the evaluated property value attached as evidence.
How to fix it
Disable auto-assign public IP on subnets and use NAT gateways for outbound access. In AWS Console: VPC > Subnets > Edit > disable Auto-assign public IP. See: https://docs.aws.amazon.com/vpc/latest/userguide/configure-subnets.html
CLI
aws ec2 modify-subnet-attribute --subnet-id "{id}" --no-map-public-ip-on-launchTerraform
resource "aws_subnet" "{name}" {
map_public_ip_on_launch = false
}
Compliance frameworks
Is your environment compliant with this rule?
CGPulse checks it — and 621 others — against your Azure and AWS accounts with read-only access.
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