Ensure 'Secure transfer required' is set to 'Enabled'

Overview

Enable data encryption in transit.

Rationale

The secure transfer option enhances the security of a storage account by only allowing requests to the storage account by a secure connection. For example, when calling REST APIs to access storage accounts, the connection must use HTTPS. Any HTTP requests will be rejected when 'secure transfer required' is enabled. When using the Azure files service, connection without encryption will fail, including scenarios using SMB 2.1, SMB 3.0 without encryption, and some flavors of the Linux SMB client. Because Azure storage doesn't support HTTPS for custom domain names, this option is not applied when using a custom domain name.

Default Value

By default, Secure transfer required is set to Disabled.

References

Remediation guidance

From Azure Console

Open the storage account in the Azure Portal using the Open in Azure button.
Under the Settings blade, go to Configuration
Set Secure transfer required to Enabled

Azure CLI

Use the below command to enable Secure transfer required for a Storage Account

az storage account update --name <storageAccountName> --resource-group <resourceGroupName> --https-only true

Multiple Remediation Paths

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

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)

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.

Azure storage accounts not enforcing HTTPS

Connectors

Microsoft Azure

Covered asset types

StorageAccount

Expected check: eq []

{
  storageAccounts(where: { NOT: { supportsHttpsTrafficOnly: true } }) {
    ...AssetFragment
  }
}