EC2 instance blocks Internet ingress to CIFS ports

# Security group without CIFS open to the Internet
resource "aws_security_group" "<example_resource_name>" {
  name   = "<example_resource_name>"
  vpc_id = "<example_resource_id>"

  ingress {
    from_port   = 139
    to_port     = 139
    protocol    = "tcp"
    cidr_blocks = ["10.0.0.0/8"] # CRITICAL: restrict CIFS (139); do not use 0.0.0.0/0
  }

  ingress {
    from_port   = 445
    to_port     = 445
    protocol    = "tcp"
    cidr_blocks = ["10.0.0.0/8"] # CRITICAL: restrict CIFS (445); do not use 0.0.0.0/0
  }
}

# CloudFormation: Security group without CIFS open to the Internet
Resources:
  <example_resource_name>:
    Type: AWS::EC2::SecurityGroup
    Properties:
      GroupDescription: SG without CIFS open to Internet
      VpcId: <example_resource_id>
      SecurityGroupIngress:
        - IpProtocol: tcp
          FromPort: 139
          ToPort: 139
          CidrIp: 10.0.0.0/8  # CRITICAL: restrict CIFS (139) to a non-Internet CIDR to avoid 0.0.0.0/0
        - IpProtocol: tcp
          FromPort: 445
          ToPort: 445
          CidrIp: 10.0.0.0/8  # CRITICAL: restrict CIFS (445) to a non-Internet CIDR to avoid 0.0.0.0/0