CloudFront distributions should have a default root object configured¶

This control checks whether an AWS CloudFront distribution is configured to return a specific object that is the default root object. The control fails if the CloudFront distribution does not have a default root object configured.

How to fix¶

Attribute default_root_object of aws_cloudfront_distribution must be non-empty.

Implementation options¶

Choose the option that matches how you manage Terraform. All options satisfy this control.

Option 1: Compliance.tf module (recommended)¶

Use the compliance.tf registry module to get this control enforced by default. This control is mapped to the frameworks shown in the tabs above. To begin, see get started with compliance.tf.

module "cloudfront" {
  source  = "nistcsfv11.compliance.tf/terraform-aws-modules/cloudfront/aws"
  version = ">=6.0.0,<7.0.0"

  comment = "My CloudFront distribution"
  default_cache_behavior = {
    target_origin_id       = "s3"
    viewer_protocol_policy = "redirect-to-https"
  }
  enabled = true
  origin = {
    s3 = {
      domain_name = "mybucket.s3.amazonaws.com"
    }
  }
}

Option 2: Open source module (terraform-aws-modules)¶

If you use terraform-aws-modules/cloudfront/aws, configure the required module inputs to satisfy this control. You can later migrate to the compliance.tf module with minimal changes because it is compatible by design.

module "cloudfront" {
  source  = "terraform-aws-modules/cloudfront/aws"
  version = ">=6.0.0,<7.0.0"

  comment = "My CloudFront distribution"
  default_cache_behavior = {
    target_origin_id       = "s3"
    viewer_protocol_policy = "redirect-to-https"
  }
  enabled = true
  origin = {
    s3 = {
      domain_name = "mybucket.s3.amazonaws.com"
    }
  }
}

Option 3: Terraform AWS provider resources¶

If you manage resources directly, configure the relevant Terraform AWS provider resources to meet this control. See docs for the resources involved: aws_cloudfront_distribution.

resource "aws_cloudfront_distribution" "this" {
  default_cache_behavior {
    allowed_methods           = ["GET", "HEAD"]
    cached_methods            = ["GET", "HEAD"]
    field_level_encryption_id = "E1EXAMPLE"

    forwarded_values {
      cookies {
        forward = "none"
      }
      query_string = false
    }

    target_origin_id       = "S3Origin"
    viewer_protocol_policy = "redirect-to-https"
  }
  default_root_object = "index.html"
  enabled             = true

  logging_config {
    bucket = "logging-bucket.s3.amazonaws.com"
  }

  origin {
    domain_name = "example.s3.amazonaws.com"
    origin_id   = "S3Origin"
  }

  restrictions {
    geo_restriction {
      locations        = ["US", "CA", "GB"]
      restriction_type = "whitelist"
    }
  }

  viewer_certificate {
    acm_certificate_arn      = "arn:aws:acm:us-east-1:123456789012:certificate/example"
    minimum_protocol_version = "TLSv1.2_2021"
    ssl_support_method       = "sni-only"
  }

  web_acl_id = "arn:aws:wafv2:us-east-1:123456789012:global/webacl/example/id"
}

Tool mappings¶

Use these identifiers to cross-reference this control across tools, reports, and evidence.

• Compliance.tf (CTF) Control: cloudfront_distribution_default_root_object_configured

• AWS Config Managed Rule: CLOUDFRONT_DEFAULT_ROOT_OBJECT_CONFIGURED

• Checkov Check: CKV_AWS_305

• Powerpipe Control: aws_compliance.control.cloudfront_distribution_default_root_object_configured