Alibaba Cloud
AWS
Google Cloud
Microsoft AzureOverview
Buckets should almost never be publicly accessible (excepting when using them to host public static websites). When configured to allow public access, anyone can read the data (objects) without having to perform any authentication or authorization. This can lead to data leaks and can potentially generate considerable costs.
If you want to grant access to certain objects to certain users, you can leverage signed URLs:
AWS
Azure
Google Cloud
Alibaba
If you want to configure the bucket for static website hosting, we recommend adding a CDN in front of it.
- https://aws.amazon.com/premiumsupport/knowledge-center/cloudfront-serve-static-website/
- https://learn.microsoft.com/en-us/azure/storage/blobs/static-website-content-delivery-network
- https://cloud.google.com/storage/docs/hosting-static-website
- https://www.alibabacloud.com/help/en/object-storage-service/latest/use-cdn-to-accelerate-access-to-oss
Remediation guidance
AWS
- https://docs.aws.amazon.com/AmazonS3/latest/userguide/access-control-block-public-access.html
Azure
- https://learn.microsoft.com/en-us/azure/storage/blobs/anonymous-read-access-prevent
Google Cloud
- https://cloud.google.com/storage/docs/access-control#public_access_prevention
Alibaba Cloud
- https://www.alibabacloud.com/help/en/object-storage-service/latest/access-and-control-overview
Multiple Remediation Paths
AWS
SERVICE-WIDE (RECOMMENDED when many resources are affected): Deploy centralized guardrails and remediation using AWS Config Conformance Packs and (if applicable) AWS Organizations SCPs.
aws configservice put-organization-conformance-pack --organization-conformance-pack-name <pack-name> --template-s3-uri s3://<bucket>/<template>.yaml
ASSET-LEVEL: Apply the resource-specific remediation steps above to only the affected assets.
PREVENTIVE: Add CI/CD policy checks (CloudFormation/Terraform validation) before deployment to prevent recurrence.
Google Cloud
SERVICE-WIDE (RECOMMENDED when many resources are affected): Enforce Organization Policies at org/folder level so new resources inherit secure defaults.
gcloud org-policies set-policy policy.yaml
ASSET-LEVEL: Use the product-specific remediation steps above for only the impacted project/resources.
PREVENTIVE: Use org policy constraints/custom constraints and enforce checks in deployment pipelines.
Azure
SERVICE-WIDE (RECOMMENDED when many resources are affected): Assign Azure Policy initiatives at management group/subscription scope and trigger remediation tasks.
az policy assignment create --name <assignment-name> --scope /subscriptions/<subscription-id> --policy-set-definition <initiative-id>
az policy remediation create --name <remediation-name> --policy-assignment <assignment-id>
ASSET-LEVEL: Apply the resource-specific remediation steps above to the listed non-compliant resources.
PREVENTIVE: Embed Azure Policy checks into landing zones and IaC workflows to block or auto-remediate drift.
References for Service-Wide Patterns
- AWS Config Conformance Packs: https://docs.aws.amazon.com/config/latest/developerguide/conformance-packs.html
- AWS Organizations SCP examples: https://docs.aws.amazon.com/organizations/latest/userguide/orgs_manage_policies_scps_examples.html
- GCP Organization Policy overview: https://cloud.google.com/resource-manager/docs/organization-policy/overview
- GCP Organization policy constraints catalog: https://cloud.google.com/resource-manager/docs/organization-policy/org-policy-constraints
- gcloud org-policies: https://cloud.google.com/sdk/gcloud/reference/org-policies
- Azure Policy overview: https://learn.microsoft.com/en-us/azure/governance/policy/overview
- Azure Policy remediation: https://learn.microsoft.com/en-us/azure/governance/policy/how-to/remediate-resources
- Azure Policy initiative structure: https://learn.microsoft.com/en-us/azure/governance/policy/concepts/initiative-definition-structure
Operational Rollout Workflow
Use this sequence to reduce risk and avoid repeated drift.
1. Contain at Service-Wide Scope First (Recommended)
- AWS: deploy/adjust organization conformance packs and policy guardrails.
aws configservice put-organization-conformance-pack --organization-conformance-pack-name <pack-name> --template-s3-uri s3://<bucket>/<template>.yaml
- Google Cloud: apply organization policy constraints at org/folder scope.
gcloud org-policies set-policy policy.yaml
- Azure: assign policy initiatives at management group/subscription scope and run remediation tasks.
az policy assignment create --name <assignment-name> --scope /subscriptions/<subscription-id> --policy-set-definition <initiative-id>
az policy remediation create --name <remediation-name> --policy-assignment <assignment-id>
2. Remediate Existing Affected Assets
- Execute the control-specific Console/CLI steps documented above for each flagged resource.
- Prioritize internet-exposed and production assets first.
3. Validate and Prevent Recurrence
- Re-scan after each remediation batch.
- Track exceptions with owner and expiry date.
- Add preventive checks in IaC/CI pipelines.
Query logic
These are the stored checks tied to this control.
Publicly Readable AWS Buckets
Connectors
Covered asset types
Expected check: eq []
{ buckets( where: { cloudProvider: "aws" publicAccessBlocked: false OR: [ { hasBucketACLGrant_SOME: { OR: [ { granteeURI: "http://acs.amazonaws.com/groups/global/AllUsers" } { granteeURI: "http://acs.amazonaws.com/groups/global/AuthenticatedUsers" } ] permission_IN: ["READ", "FULL_CONTROL"] } } { bucketPolicy: { statements_SOME: { effect: "Allow" OR: [ { actions_INCLUDES: "s3:GetObject" } { actions_INCLUDES: "s3:ListObjects" } { actions_INCLUDES: "s3:ListObjectsV2" } { actions_INCLUDES: "s3:*" } { actions_INCLUDES: "*" } ] principals_INCLUDES: "AWS|*" } } } ] } ) {...AssetFragment} } Publicly Readable Azure Blob Containers
Connectors
Covered asset types
Expected check: eq []
{
blobContainers(
where: {
cloudProvider: "azure"
publicAccessBlocked: false
publicAccess_IN: ["Blob", "Container"]
}
) {...AssetFragment}
}
Publicly Readable Alibaba Buckets
Connectors
Covered asset types
Expected check: eq []
{ buckets( where: { cloudProvider: "alibaba" publicAccessBlocked: false OR: [ { acl_IN: ["public-read"] } { bucketPolicy: { statements_SOME: { effect: "Allow" OR: [ { actions_INCLUDES: "oss:GetObject" } { actions_INCLUDES: "oss:ListObjects" } { actions_INCLUDES: "oss:GetObjectVersion" } { actions_INCLUDES: "oss:*" } { actions_INCLUDES: "*" } ] principals_INCLUDES: "*" } } } ] } ) {...AssetFragment} } Publicly Readable Google Cloud Buckets
Connectors
Covered asset types
Expected check: eq []
{ buckets( where: { cloudProvider: "gcp" publicAccessBlocked: false iamBindings_SOME: { OR: [ { members_INCLUDES: "allUsers" } { members_INCLUDES: "allAuthenticatedUsers" } ] role: { OR: [ { permissions_INCLUDES: "storage.objects.get" } { permissions_INCLUDES: "storage.objects.list" } { permissions_INCLUDES: "storage.objects.*" } ] } } } ) {...AssetFragment} } 
