Ensure that Activity Log Alert exists for Create or Update Network Security Group

Remediate from Azure Portal

1. Navigate to the Monitor blade.
2. Select Alerts.
3. Select Create.
4. Select Alert rule.
5. Choose a subscription.
6. Select Apply.
7. Select the Condition tab.
8. Click See all signals.
9. Select Create or Update Network Security Group (Network Security Group).
10. Click Apply.
11. Select the Actions tab.
12. Click Select action groups to select an existing action group or Create action group to create a new one.
13. Follow the prompts to choose or create an action group.
14. Select the Details tab.
15. Select a Resource group, and provide an Alert rule name and an optional Alert rule description.
16. Click Review + create.
17. Click Create.

Remediate from Azure CLI

az monitor activity-log alert create --resource-group "<resource_group_name>" --condition category=Administrative and operationName=Microsoft.Network/networkSecurityGroups/write and level=verbose --scope "/subscriptions/<subscription ID>" --name "<activity_log_rule_name>" --subscription <subscription_id> --action-group <action_group_ID>

Remediate from PowerShell

Create the Conditions object.

$conditions = @()
$conditions += New-AzActivityLogAlertAlertRuleAnyOfOrLeafConditionObject -Equal Administrative -Field category
$conditions += New-AzActivityLogAlertAlertRuleAnyOfOrLeafConditionObject -Equal Microsoft.Network/networkSecurityGroups/write -Field operationName
$conditions += New-AzActivityLogAlertAlertRuleAnyOfOrLeafConditionObject -Equal Verbose -Field level

Retrieve the Action Group information, store it in a variable, and then create the Actions object.

$actionGroup = Get-AzActionGroup -ResourceGroupName <resource_group_name> -Name <action_group_name>
$actionObject = New-AzActivityLogAlertActionGroupObject -Id $actionGroup.Id

Create the Scope object

$scope = "/subscriptions/<subscription id>"

Create the Activity Log Alert Rule for Microsoft.Network/networkSecurityGroups/write

New-AzActivityLogAlert -Name "<activity_log_alert_rule_name>" -ResourceGroupName "<resource_group_name>" -Condition $conditions -Scope $scope -Location global -Action $actionObject -Subscription <subscription_ID> -Enabled $true

Service-wide remediation

Recommended when many resources are affected: fix the platform baseline first so new resources inherit the secure setting, then remediate the existing flagged resources in batches.

Azure

Use management group or subscription Azure Policy assignments, remediation tasks where supported, landing-zone standards, and IaC modules so drift is prevented at scale.

Operational rollout

1. Fix the baseline first at the account, subscription, project, cluster, or tenant scope that owns this control.
2. Remediate the currently affected resources in batches, starting with internet-exposed and production assets.
3. Re-scan and track approved exceptions with an owner and expiry date.