Cis Azure Foundations 8.1.3.1

8.1.3.1 Ensure that Defender for Servers is set to 'On' (Automated)

Description

The Defender for Servers plan in Microsoft Defender for Cloud reduces security risk by providing actionable recommendations to improve and remediate machine security posture. Defender for Servers also helps to protect machines against real-time security threats and attacks. Defender for Servers offers two paid plans: Plan 1 and Plan 2.

Rationale

Enabling Defender for Servers allows for greater defense-in-depth, with threat detection provided by the Microsoft Security Response Center (MSRC).

Impact

Enabling Defender for Servers in Microsoft Defender for Cloud incurs an additional cost per resource. Plan 1: Subscription only. Plan 2: Subscription and workspace.

Audit Procedure

From Azure Portal:

1. Go to Microsoft Defender for Cloud.
2. Under Management, select Environment settings.
3. Click on a subscription name.
4. Select Defender plans in the left pane.
5. Under Cloud Workload Protection (CWP), locate Servers in the Plan column, ensure Status is set to On.
6. Repeat steps 1-5 for each subscription.

From Azure CLI:

az security pricing show -n VirtualMachines --query pricingTier

If the tenant is licensed and enabled, the output will indicate Standard.

From PowerShell:

Get-AzSecurityPricing -Name 'VirtualMachines' | Select-Object Name,PricingTier

If the tenant is licensed and enabled, the -PricingTier parameter will indicate Standard.

From Azure Policy:

• Policy ID: 4da35fc9-c9e7-4960-aec9-797fe7d9051d - Name: 'Azure Defender for servers should be enabled'

Expected Result

The pricing tier for VirtualMachines should be Standard.

Remediation

From Azure Portal:

1. Go to Microsoft Defender for Cloud.
2. Under Management, select Environment settings.
3. Click on a subscription name.
4. Click Defender plans in the left pane.
5. Under Cloud Workload Protection (CWP), locate Servers in the Plan column, set Status to On.
6. Select Save.
7. Repeat steps 1-6 for each subscription requiring remediation.

From Azure CLI:

az security pricing create -n VirtualMachines --tier 'standard'

From PowerShell:

Set-AzSecurityPricing -Name 'VirtualMachines' -PricingTier 'Standard'

Default Value

By default, the Defender for Servers plan is disabled.

References

1. https://learn.microsoft.com/en-us/azure/defender-for-cloud/defender-for-servers-overview
2. https://learn.microsoft.com/en-us/azure/defender-for-cloud/plan-defender-for-servers
3. https://learn.microsoft.com/en-us/rest/api/defenderforcloud/pricings/list
4. https://learn.microsoft.com/en-us/rest/api/defenderforcloud/pricings/update
5. https://learn.microsoft.com/en-us/powershell/module/az.security/get-azsecuritypricing
6. https://learn.microsoft.com/en-us/powershell/module/az.security/set-azsecuritypricing

Profile

• Level 2