Uniform Bucket-Level Access Not Enforced

ID: gcloud-org-uniform-bucket-access

Severity: medium

Author: princechaddha

Tags: cloud,devops,gcp,gcloud,resourcemanager,security,storage,bucket,gcp-cloud-config

Description

Ensure that “Enforce uniform bucket-level access” policy is enabled for your Google Cloud Platform (GCP) organization in order to enforce uniform bucket-level access for all Google Cloud Storage buckets available in your organization. Enforcing uniform bucket-level access disables Access Control Lists (ACLs) for all Cloud Storage resources (buckets and objects) so that access is granted exclusively through Cloud IAM service.

YAML Source

id: gcloud-org-uniform-bucket-access

info:
  name: Uniform Bucket-Level Access Not Enforced
  author: princechaddha
  severity: medium
  description: |
    Ensure that "Enforce uniform bucket-level access" policy is enabled for your Google Cloud Platform (GCP) organization in order to enforce uniform bucket-level access for all Google Cloud Storage buckets available in your organization. Enforcing uniform bucket-level access disables Access Control Lists (ACLs) for all Cloud Storage resources (buckets and objects) so that access is granted exclusively through Cloud IAM service.
  impact: |
    Without enforced uniform bucket-level access, buckets may use legacy ACLs which are less secure and more complex to manage than Cloud IAM permissions, potentially leading to misconfigured access controls.
  remediation: |
    Enable the "Enforce uniform bucket-level access" policy at the organization level using the 'gcloud alpha resource-manager org-policies enable-enforce' command with the storage.uniformBucketLevelAccess constraint.
  reference:
    - https://www.trendmicro.com/cloudoneconformity/knowledge-base/gcp/ResourceManager/enforce-uniform-bucket-level-access-constraint.html
    - https://cloud.google.com/storage/docs/uniform-bucket-level-access
  tags: cloud,devops,gcp,gcloud,resourcemanager,security,storage,bucket,gcp-cloud-config

flow: |
  code(1)
  for(let orgId of iterate(template.orgIds)){
    set("orgId", orgId)
    code(2)
  }

self-contained: true

code:
  - engine:
      - sh
      - bash
    source: |
      gcloud organizations list --format="json(name)"

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

  - engine:
      - sh
      - bash
    source: |
      gcloud alpha resource-manager org-policies describe storage.uniformBucketLevelAccess --organization=$orgId --effective --format="json(booleanPolicy)"

    matchers:
      - type: word
        words:
          - "{}"

    extractors:
      - type: dsl
        dsl:
          - '"Organization " + orgId + " has not enforced uniform bucket-level access for Cloud Storage buckets"'
# digest: 4a0a004730450220226a887a6d10ad64e45d6a72909b0fccb4bb7c08397c15b7427ae9d4dff47c7b022100e57ea92a4ed2f9691299cd42378268b5436c6cd6230069f6a67066d6b2ee14b9:922c64590222798bb761d5b6d8e72950

Guide to check the vulnerabilities

This template is used to detect vulnerabilities in web applications. It can be used with the Nuclei tool to scan for specific patterns or behaviors.

$ nuclei -u "URL" -t "cloud/gcp/resourcemanager/gcloud-org-uniform-bucket-access.yaml"

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