Ensure That 'Notify about alerts with the following severity' is Set to 'High'

Description:

Enables emailing security alerts to the subscription owner or other designated security contact.

Rationale:

Enabling security alert emails ensures that security alert emails are received from Microsoft. This ensures that the right people are aware of any potential security issues and are able to mitigate the risk.

From Azure Portal

1. From Azure Home select the Portal Menu
2. Select 'Microsoft Defender for Cloud'
3. Click on 'Environment Settings'
4. Click on the appropriate Management Group, Subscription, or Workspace
5. Click on 'Email notifications'
6. Under 'Notification types', check the check box next to 'Notify about alerts with the following severity (or higher):' and select 'High' from the drop down menu
7. Click 'Save'

From Azure CLI

Use the below command to set 'Send email notification for high severity alerts' 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 data below, replacing 'validEmailAddress' with a single email address or multiple comma-separated email addresses:

{
"id": "/subscriptions//providers/Microsoft.Security/securityContacts/default1",
"name": "default1",
"type": "Microsoft.Security/securityContacts",
"properties": {
"email": "",
"alertNotifications": "On",
"alertsToAdmins": "On"
}
}