rules:
- id: aws-transfer-server-is-public
  patterns:
  - pattern: |
      resource "aws_transfer_server" $ANYTHING {
        ...
      }
  - pattern-not-inside: |
      resource "aws_transfer_server" $ANYTHING {
        ...
        endpoint_type = "VPC"
        ...
      }
  message: >-
    Transfer Server endpoint type should not have public or null configured in order to block public access.
    To fix this, set your `endpoint_type` to
    `"VPC"`.
  metadata:
    category: security
    technology:
    - terraform
    - aws
    owasp:
    - A05:2017 - Broken Access Control
    - A01:2021 - Broken Access Control
    cwe:
    - 'CWE-284: Improper Access Control'
    references:
    - https://owasp.org/Top10/A01_2021-Broken_Access_Control
    subcategory:
    - audit
    likelihood: LOW
    impact: LOW
    confidence: LOW
  languages: [hcl]
  severity: WARNING