azure-appservice-backup-retention-missing: Azure App Service Backup Retention Not Configured

id: azure-appservice-backup-retention-missing
info:
  name: Azure App Service Backup Retention Not Configured
  author: princechaddha
  severity: medium
  description: |
    Ensure that your Microsoft Azure App Services applications have a sufficient daily backup retention period configured for scheduled backups, in order to follow security and regulatory requirements. Prior to running this rule by the Cloud Conformity engine, the backup retention period must be configured in the rule settings, on the Cloud Conformity account dashboard. A retention value of 0 will keep backup files indefinitely.
  impact: |
    Lack of a backup retention configuration can lead to non-compliance with security and regulatory requirements and potential data loss.
  remediation: |
    Configure the daily backup retention period for Azure App Services applications in the Cloud Conformity account dashboard to meet security and compliance requirements.
  reference:
    - https://docs.microsoft.com/en-us/azure/app-service/manage-backup
  tags: cloud,devops,azure,microsoft,appservice,azure-cloud-config

flow: |
  code(1);
  for (let AppServiceData of iterate(template.appServiceList)) {
    AppServiceData = JSON.parse(AppServiceData);
    set("name", AppServiceData.name);
    set("resourceGroup", AppServiceData.resourceGroup);
    code(2);
  }

self-contained: true
code:
  - engine:
      - sh
      - bash
    source: |
      az webapp list --output json --query '[*].{name:name, resourceGroup:resourceGroup}'

    extractors:
      - type: json
        name: appServiceList
        internal: true
        json:
          - '.[]'

  - engine:
      - sh
      - bash
    source: |
      az webapp config backup show --webapp-name $name --resource-group $resourceGroup --query 'backupSchedule.retentionPeriodInDays' --output json

    matchers:
      - type: word
        part: stderr
        words:
          - "Backup configuration not found"

    extractors:
      - type: dsl
        dsl:
          - 'name + " in " + resourceGroup + " does not have a backup retention period configured"'
# digest: 490a00463044022057d177778b77e8212e836670e2156b5330cd2608fc66aa850a7a0a48c98422620220450ed59da03206da06e6a4669ceaf29660fa18b49b8306287cbd7a5b186a7bbf:922c64590222798bb761d5b6d8e72950

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