rules:
- id: aws-insecure-cloudfront-distribution-tls-version
  patterns:
  - pattern: |
      resource "aws_cloudfront_distribution" $ANYTHING {
        ...
        viewer_certificate {
          ...
        }
        ...
      }
  - pattern-not-inside: |
      resource "aws_cloudfront_distribution" $ANYTHING {
        ...
        viewer_certificate {
          ...
          minimum_protocol_version = "TLSv1.2_2018"
          ...
        }
        ...
      }
  - pattern-not-inside: |
      resource "aws_cloudfront_distribution" $ANYTHING {
        ...
        viewer_certificate {
          ...
          minimum_protocol_version = "TLSv1.2_2019"
          ...
        }
        ...
      }
  - pattern-not-inside: |
      resource "aws_cloudfront_distribution" $ANYTHING {
        ...
        viewer_certificate {
          ...
          minimum_protocol_version = "TLSv1.2_2021"
          ...
        }
        ...
      }
  message: >-
    Detected an AWS CloudFront Distribution with an insecure TLS version.
    TLS versions less than 1.2 are considered insecure because they
    can be broken. To fix this, set your `minimum_protocol_version` to
    `"TLSv1.2_2018", "TLSv1.2_2019" or "TLSv1.2_2021"`.
  metadata:
    category: security
    technology:
    - terraform
    - aws
    owasp:
    - A03:2017 - Sensitive Data Exposure
    - A02:2021 - Cryptographic Failures
    cwe:
    - 'CWE-326: Inadequate Encryption Strength'
    references:
    - https://owasp.org/Top10/A02_2021-Cryptographic_Failures
    subcategory:
    - vuln
    likelihood: MEDIUM
    impact: MEDIUM
    confidence: MEDIUM
  languages: [hcl]
  severity: WARNING