Ensure 'Additional email addresses' is configured with a security contact email

Overview

Microsoft Defender for Cloud emails the subscription owners whenever a high-severity alert is triggered for their subscription. You should provide a security contact email address as an additional email address.

Rationale

Microsoft Defender for Cloud emails the Subscription Owner to notify them about security alerts. Adding your Security Contact's email address to the 'Additional email addresses' field ensures that your organization's Security Team is included in these alerts. This ensures that the appropriate professionals are aware of any potential compromise in order to mitigate the risk in a timely manner.

Default Value

By default, there are no additional email addresses entered.

References

Remediation guidance

From Azure Console

Open Microsoft Defender for Cloud | Environment settings
Select the appropriate Management Group, Subscription, or Workspace
Select Email notifications
Under Email recipients, in the Additional email addresses field, enter a valid security contact email address (or multiple, separated by comma)
Select Save

Using Azure Command Line Interface

Use the below command to set Security contact emails to On.

az account get-access-token --query "{subscription:subscription,accessToken:accessToken}" --out tsv | xargs -L1 bash -c 'curl -X PUT -H "Authorization: Bearer $1" -H "Content-Type: application/json"
https://management.azure.com/subscriptions/$0/providers/Microsoft.Security/securityContacts/default1?api-version=2017-08-01-preview -d@"input.json"'

Where input.json contains the Request body json data as mentioned below. Replace <validEmailAddress> with one email address or multiple comma-separated email addresses.

{
    "id": "/subscriptions/<subscriptionID>/providers/Microsoft.Security/securityContacts/default",
    "name": "default",
    "type": "Microsoft.Security/securityContacts",
    "properties": {
        "email": "<validEmailAddress>",
        "alertNotifications": "On",
        "alertsToAdmins": "On"
    }
}

Additional Information

Excluding any of the entries in the input.json properties block disables the specific setting by default.

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 connectors without security contact additional email addresses

Connectors

Microsoft Azure

Covered asset types

Connector

Expected check: eq []

{
  connectors(
    where: {
      OR: [
        { securityContacts_SOME: null }
        { securityContacts_SOME: { email: null } }
        { securityContacts_SOME: { email: "" } }
      ]
    }
  ) {
    ...AssetFragment
  }
}