Microsoft Defender for Cloud
Cloud and workloads

Enable agentless machine scanning

In brief

The article now details supported Azure, AWS, and GCP machines, Kubernetes coverage, capabilities by plan, scan limitations, unsupported configurations, permissions, and the 24-hour schedule. It also directs administrators to review coverage before enabling scanning.

What Defender admins need to know

Administrators can use the updated guidance to verify coverage and limitations before enabling agentless scanning; no required change is stated.

Summaries are generated from the documentation change itself.

Documentation change

The comparison below shows only the changed extract. Use the full-page view for complete context.


title: Enable agentless machine scanning description: RunLearn what agentless scanning on Virtual Machines (VMs) for vulnerabilitiescovers, review supported Azure, AWS, and threatsGCP machines, and enable scanning in Microsoft Defender for Cloud. ms.topic: how-to ms.date: 06/02/08/24/2026 ms.custom: sfi-image-nochangenochange, msecd-doc-authoring-1013

#customer intent: As a security administrator, I want to enable agentless scanning for VMs so that I can identify vulnerabilities and threats without impacting performance. ai-usage: ai-assisted

Enable agentless machine scanning

Agentless machine scanning helps you discover vulnerabilities, secrets, malware signals, and software inventory across cloud machines without deploying endpoint agents. In Microsoft Defender for Cloud, this capability runs through your cloud connectors so security teams can scale coverage with low operational overhead and minimal performance impact.

This article explains the supported environments, important coverage limitations, and how to enable and manage scanning across Azure, AWS, and GCP environments so you can onboard protection quickly and start investigating findings. If your environment has plan or permission dependencies, review prerequisitesGCP.

Agentless machine scanning in Microsoft Defender for Cloud improves the security posture of machines connected to Defender for Cloud. Agentless machine scanning includes capabilities such as scanning for software inventory, vulnerabilities, secrets, and malware.

  • Agentless scanning doesn't require installed agents or network connectivity, and it doesn't affect machine performance.
  • You can turn agentless machine scanning on or off, but you can't disable individual capabilities.
  • Scans only run on VMs that are running. VMs that are off during a scan aren't scanned.
  • The scan runs once every 24 hours on a nonconfigurable schedule once every 24 hours.
schedule.

What agentless scanning covers

When you turn on The following table shows what each capability provides and which plans include it.

CapabilityWhat it providesDefender CSPMDefender for Servers Plan 2 or Defender cloud security posture management (Defender CSPM), agentless machine scanning is enabled by default. If needed, use the procedures in this article to enable agentless machine scanning manually.

Prerequisites

RequirementDetails
PlanSoftware inventory To use agentless scanning, the Defender cloud security posture management (Defender CSPM) plan or Defender for Servers Plan 2 must be enabled.

When you enable agentless scanning
Lists software found on either plan, the setting is enabled for both plans.supported machine disks.
YesYes
Malware scanningVulnerability assessment Malware scanning is only available when Defender for Servers Plan 2 is enabled.

For malware scanning of Kubernetes node VMs, either Defender for Servers Plan 2 or
Identifies known vulnerabilities associated with the Defender for Containers plan is required.discovered software.
YesYes
Supported machinesSecrets scanning YouFinds plaintext secrets stored on supported machine disks.YesYes
Malware scanningDetects malicious files and generates security alerts for detected threats. Review Malware scanning coverage and limitations.NoYes

Agentless scanning has one setting for each connected environment, such as an Azure subscription, AWS account, or GCP project. The plans enabled for that environment determine which agentless capabilities are available. Individual agentless capabilities can't be turned on or off separately.

Supported machines and scan coverage

Scan timing and machine state

Condition Coverage
The machine is running during its scheduled scan The machine is eligible to be scanned.
The machine is stopped or deallocated during its scheduled scan The machine isn't scanned during that cycle. Results can remain missing or outdated until the machine is running during a later scheduled cycle.
Agentless scanning was just enabled or connector permissions were updated Allow up to 24 hours for the next scheduled scan before troubleshooting missing results.

Azure VM requirements

Agentless scanning supports Azure standard VMs and virtual machine scale sets that use flexible orchestration, subject to these limits:

Requirement Supported coverage
Combined size of the operating system disk and all data disks is 4 TB or less The operating system disk and supported data disks can be scanned.
Combined size of the operating system disk and all data disks exceeds 4 TB Only the operating system disk is scanned, and only when that disk is less than 4 TB. Data disks aren't scanned.
The VM has 14 disks or fewer The VM is within the supported disk-count limit. VMs with more than 14 disks aren't supported.
Disks use platform-managed keys Supported.
Managed disks use customer-managed keys Supported after you grant the additional Key Vault permissions described in Azure VMs with customer-managed keys.

AWS requirements

Agentless scanning supports:

  • Amazon EC2 instances and instances in Auto Scaling groups.
  • Unencrypted disks.
  • Disks encrypted with platform-managed or customer-managed keys.

Amazon Machine Images (AMIs) that require third-party licensing, including applicable AWS Marketplace images, aren't supported.

GCP requirements

Agentless scanning supports Compute Engine instances and instance groups, both managed and unmanaged, with Google-managed encryption keys or customer-managed encryption keys (CMEK).

GCP organization policies can prevent Defender for Cloud from creating or accessing the snapshots required for scanning. If no results appear within 24 hours, review Resolve an agentless scan error for GCP.

Malware scanning coverage and limitations

Agentless malware scanning provides periodic, point-in-time visibility rather than continuous or real-time protection. The amount and type of content on a VM can affect scan coverage.

Compressed package limits

A malware scan can complete with partial VM coverage when a compressed package meets any of these conditions:

ConditionPartial-coverage threshold
Compressed package sizeLarger than 1 GB
Files in a compressed packageMore than 10,000 files
Nested archive depthMore than five archive levels

File-count planning targets

For a lower risk of partial coverage, use these planning targets for the total number of files eligible for malware scanning across the VM:

Operating systemPlanning target
WindowsUp to approximately 300,000 files
LinuxUp to approximately 500,000 files

Workloads that create or modify approximately 200,000 files or more between scans can also have an increased risk of partial coverage.

Files that might not be scanned

The following files might not be scanned:

  • Empty files.
  • Files that are inaccessible or no longer available at scan time.
  • Files with unsupported operating-system attributes, including system, offline, operating-system-level compressed, or reparse-point files.

What partial coverage means

Partial coverage doesn't discard the scan results. Detections from content that was successfully scanned are still reported.

To improve coverage:

  • Reduce large file collections where operationally appropriate.
  • Extract or split compressed packages that exceed the package thresholds.
  • Make sure important files are accessible at scan time.

Limitations and unsupported configurations

Agentless scanning doesn't support the following configurations.

Category Unsupported configuration Coverage consequence
Azure disk type UltraSSD_LRS, PremiumV2_LRS, or Azure Kubernetes Service (AKS) ephemeral OS disks If any disk attached to the VM uses one of these disk types, the VM isn't scanned.
Resource type Databricks VMs The VM isn't supported for agentless scanning.
File system UFS (Unix File System), ReFS (Resilient File System), or ZFS (ZFS Member) If any disk uses one of these file systems, the VM isn't scanned.
RAID or block-storage format OracleASM (Oracle Automatic Storage Management), DRBD (Distributed Replicated Block Device), or Linux_Raid_Member If any disk uses one of these formats, the VM isn't scanned.
Integrity mechanism or partition DM_Verity_Hash or swap If any disk contains one of these configurations, the VM isn't scanned.

Before you begin

Verify the following requirements:

  • Plan: Agentless scanning requires Defender CSPM or Defender for Servers Plan 2. Agentless malware scanning is available only with Defender for Servers Plan 2.
  • Connected environment: The Azure subscription, AWS account, or GCP project or organization must be connected to Microsoft Defender for Cloud.
  • Machine support: Confirm that the machine and its disks meet the requirements in Supported machines and scan coverage and aren't listed under Limitations and unsupported configurations.
  • Permissions: Review the permissions used by agentless scanning.
  • Customer-managed encryption: For Azure virtualdisks encrypted with customer-managed keys, grant the additional Key Vault permissions described in Azure VMs with customer-managed keys. AWS and GCP connector setup includes the required permissions for their key-management services.

Enable agentless scanning

Use the rollout guidance in this section, and then follow the procedure for each cloud environment.

Plan your rollout

A phased rollout helps you confirm permissions, identify unsupported machines, and establish a repeatable process before enabling agentless scanning across a large environment.

Benefits of a phased rollout

  • Find coverage gaps early: Identify machines (VMs), Amazon Web Services (AWS) Elastic Compute Cloud (EC2) instances,that exceed disk limits or use unsupported configurations before broad deployment.
  • Validate permissions: Confirm that disk snapshots and Google Cloud Platform (GCP) compute instances without installing an agent, if theycustomer-managed encryption keys can be accessed as expected.
  • Set clear expectations: Verify which inventory, vulnerability, secrets, and malware results should appear for each enabled plan.
  • Reduce repeated work: Use the validated connector and permission configuration as the pattern for additional environments.

Guidelines for a successful rollout

GuidelineRecommended approach
Choose a representative test environmentInclude common machine types and any customer-managed encryption, large disks, multiple data disks, or scale sets used in your organization.
Review support before enablingCheck disk size, disk count, disk type, file system, encryption, and machine power-state requirements. Record machines that aren're connected to Microsoft Defender for Cloudt supported.
Assess malware content scaleFor malware scanning, compare file counts, file-change volume, and compressed packages with the coverage guidance.
Azure VMsDefine the expected results Agentless scanning is availableDecide which software inventory, vulnerability, secrets, or malware results you expect based on Azure standard VMs with:

- Maximum total disk size of 4 TB (sum of all disks). If this limit is exceeded, only
the OS disk is scanned whenplan enabled for the OS disk is less than 4 TB.
- Maximum number of disks allowed: 14
- Virtual machine scale set - Flex

Support for disks that are:
- Unencrypted
- Encrypted (managed disks using Azure Storage encryption with platform-managed keys (PMK))
- Encrypted with customer-managed keys.
environment.
AWSAllow for the scan schedule Agentless scanning is available on EC2, Auto Scale instances, and disks that are unencrypted, encrypted (PMK), and encrypted (CMK). AMIs requiring third-party licensing, for example from AWS Marketplace, are not supported.Wait up to 24 hours after enablement or permission changes before assessing the results.
GCPVerify results, not only the setting Agentless scanning is available on compute instances, instance groups (managed and unmanaged), with Google-managed encryption keys, and customer-managed encryption key (CMEK)Confirm that results appear for the expected test machines. An enabled setting alone doesn't confirm successful coverage.
Kubernetes nodesResolve exceptions before expanding Agentless scanning for vulnerabilities and malware in Kubernetes node VMs is available.

For vulnerability assessment, Defender for Servers Plan 2,
Correct missing permissions or connector configuration. Document machines that remain outside the Defender for Containers plan, or the Defender cloud security posture management (Defender CSPM) plan is required.

For malware scanning, Defender for Servers Plan 2 or Defender for Containers is required.
supported configuration.
PermissionsRoll out in manageable groups Review the permissions used by Defender for Cloud for agentless scanning.
UnsupportedDisk type - If any of the VM's disks are on this list, the VM isn't scanned:
- UltraSSD_LRS
- PremiumV2_LRS
-Enable additional Azure Kubernetes Service (AKS) Ephemeral OS Disks

Resource type:
- Databricks VM

File systems:
- UFS (Unix File System)
- ReFS (Resilient File System)
- ZFS (ZFS Member)

RAIDsubscriptions, AWS accounts, or GCP projects in batches and Block storage formats:
- OracleASM (Oracle Automatic Storage Management)
- DRBD (Distributed Replicated Block Device)
- Linux_Raid_Member

Integrity mechanisms:
- DM_Verity_Hash
- Swapverify each batch before continuing.

Recommended rollout sequence

  1. Select a representative Azure subscription, AWS account, or GCP project.

  2. Review its machines against the supported coverage and limitation tables on this page.

  3. If malware scanning is required, review the file-count and compressed-package guidance.

  4. Confirm that the required plan, connector, and encryption permissions are in place.

  5. Define which results you expect to see for the test machines.

  6. Enable agentless scanning on and allow up to 24 hours for the scheduled scan.

  7. Verify that software inventory or vulnerability results appear. To validate malware scanning, follow Test agentless malware scanning.

  8. Resolve permission, connector, or support issues.

  9. Repeat the process for the next group of subscriptions, accounts, or projects.

Azure

To enable agentless scanning on Azure:for an Azure subscription:

  1. In Defender for Cloud, open Environment settings.

  2. Select the relevant subscription.

  3. For either the Defender CSPM plan, or Defender for Servers Plan 2,2, select Settings.

    :::::image type="content" source="media/enable-vulnerability-assessment-agentless/defender-plan-settings-azure.png" alt-text="Screenshot of the settings link for the settings of the Defender plans forin an Azure accounts.subscription." lightbox="media/enable-vulnerability-assessment-agentless/defender-plan-settings-azure.png":::

  4. In Settings and monitoring,monitoring, turn on Agentless scanning for machines.

    :::image type="content" source="media/enable-vulnerability-assessment-agentless/turn-on-agentless-scanning-azure.png" alt-text="Screenshot of settings and monitoring screenthe setting used to turn on agentless scanning.scanning for Azure machines." lightbox="media/enable-vulnerability-assessment-agentless/turn-on-agentless-scanning-azure.png":::

  5. Select Save.

Enable

Allow up to 24 hours for Azure VMs with CMK encrypted disks

To enable agentless scanning for the next scheduled scan. If results don't appear, use the troubleshooting checklist.

Azure VMs with customer-managed key (CMK) encrypted disks:keys

For agentless scanning of Azure VMs with CMKdisks encrypted disks, you need to grantby customer-managed keys require additional Key Vault permissions. These permissions allow Defender for Cloud extra permissions on Key Vaults used for CMK encryption for the VMs, to create and examine a secure copy of the disks.encrypted disk.

  1. To manually assign theAssign permissions on a Key Vault:

    • to Key vaults with non-RBAC permissions: Assign "Microsoft Defender for Cloud Servers Scanner Resource Provider" ( with application ID 0c7668b5-3260-4ad0-9f53-34ed54fa19b2) these permissions:.
      • For a key vault that uses access policies: Grant Get, Wrap Key Get,, and Unwrap Key Wrap, Key Unwrap. permissions.
      • Key vaults using RBAC permissionsFor a key vault that uses Azure role-based access control (RBAC):: Assign "Microsoft Defender for Cloud Servers Scanner Resource Provider” (0c7668b5-3260-4ad0-9f53-34ed54fa19b2) the Key Vault Crypto Service Encryption User built-in role.
    • To assign these permissions at scale foracross multiple Key Vaults, use the agentless scanning CMK support script.

Enable agentless scanning on

AWS

To enable agentless scanning on AWS:for an AWS account:

  1. In Defender for Cloud, open Environment settings.

  2. Select the relevant AWS account.

  3. For either Defender cloud security posture management (Defender CSPM)CSPM or Defender for Servers Plan 2,2, select Settings.

    :::::image type="content" source="media/enable-vulnerability-assessment-agentless/defender-plan-settings-aws.png" alt-text="Screenshot of the settings link for the settings of the Defender plans forin an AWS accounts.account." lightbox="media/enable-vulnerability-assessment-agentless/defender-plan-settings-aws.png":::

    When you enable agentless scanning on either plan, the setting applies to both plans.

  4. In the settings pane, turnTurn on Agentless scanning for machines.

    :::::image type="content" source="media/enable-vulnerability-assessment-agentless/agentless-scan-on-aws.png" alt-text="Screenshot of the agentless scanning statussetting for an AWS accounts.account." lightbox="media/enable-vulnerability-assessment-agentless/agentless-scan-on-aws.png":::

  5. Select Save and Next: Configure Access.

  6. Download the CloudFormation template.

  7. UsingCreate the downloaded CloudFormation template, create the stack in AWS as instructed on screen. by following the on-screen instructions.

  8. If you're onboarding aan AWS management account, you need to rundeploy the CloudFormation template as both as Stacka stack and asa StackSet. Connectors will be created for the member accounts up to 24 hours after the onboarding.

  9. Select Next: Review and generate.

  10. Select, and then select Update.

After you enable agentless scanning, softwareMember-account connectors can take up to 24 hours to be created. Software inventory and vulnerability information are updatedupdate automatically in Defender for Cloud.after scanning begins.

Enable agentless scanning on

GCP

To enable agentless scanning on Google Cloud Platform (GCP):for a GCP project or organization:

  1. In Defender for Cloud, selectopen Environment settings.

  2. Select the relevant GCP project or organization.

  3. For either Defender cloud security posture management (Defender CSPM)CSPM or Defender for Servers Plan 2,2, select Settings.

    :::::image type="content" source="media/enable-agentless-scanning-vms/gcp-select-plan.png" alt-text="Screenshot that shows where to select theof selecting a Defender plan for a GCP projects.project." lightbox="media/enable-agentless-scanning-vms/gcp-select-plan.png":::

  4. Set Agentless scanning to On.

    :::::image type="content" source="media/enable-agentless-scanning-vms/gcp-select-agentless.png" alt-text="Screenshot that shows where to selectof the agentless scanning.scanning setting for a GCP project." lightbox="media/enable-agentless-scanning-vms/gcp-select-agentless.png":::

  5. Select Save and Next: Configure Access.

  6. Copy the onboarding script.

  7. Runand run the onboarding script inat the intended GCP organization/organization or project scope (GCP portal or gcloud CLI).scope.

  8. Select Next: Review and generate.

  9. Select, and then select Update.

Allow up to 24 hours for the next scheduled scan. If results don't appear, check whether a GCP organization policy is restricting disk, image, or snapshot access.

Next stepTroubleshoot missing or incomplete results

[!div class="nextstepaction"] Agentless scanning runs once every 24 hours. After enabling scanning or changing permissions, allow up to 24 hours before troubleshooting missing results.

No machines are scanned

DoneActionGuidance
Check the planConfirm that Defender CSPM or Defender for Servers Plan 2 is enabled.
Check the settingIn Environment settings, turn on Agentless scanning for machines.
Check the connectionConfirm that the Azure subscription, AWS account, or GCP project or organization is connected to Defender for Cloud.
Check connector permissionsConfirm that the cloud connector setup completed successfully and includes the required permissions.
Wait for a scan cycleKeep the machines running and allow up to 24 hours for results.

Some Azure VMs aren't scanned

DoneActionGuidance
Check the power stateConfirm that each affected VM was running during a scheduled scan cycle.
Count attached disksVMs with more than 14 disks aren't supported.
Calculate total disk sizeAdd the provisioned size of the operating system disk and all data disks. If the total exceeds 4 TB, only an operating system disk smaller than 4 TB can be scanned.
Check disk typesA VM isn't scanned if any disk uses UltraSSD_LRS, PremiumV2_LRS, or an AKS ephemeral OS disk.
Check the resource and storage formatDatabricks VMs and the listed unsupported file systems, RAID formats, and integrity mechanisms aren't scanned.
Check encryption permissionsFor disks encrypted with customer-managed keys, verify the required Key Vault permissions.

Only the Azure VM operating system disk is scanned

DoneActionGuidance
Calculate total disk sizeAdd the provisioned size of the operating system disk and all data disks.
Confirm the expected coverageIf the total exceeds 4 TB, only the operating system disk is scanned, and only when that disk is less than 4 TB.
Address the remaining coverageDocument the data disks as outside agentless coverage and apply your organization's approved protection method. Don't reconfigure production disks solely to meet the scanning limit.

Azure VMs with customer-managed-key encrypted disks aren't scanned

DoneActionGuidance
Find the encryption keyIdentify the Key Vault that contains the key used to encrypt the disks.
Find the scanner identityLocate Microsoft Defender for Cloud Servers Scanner Resource Provider with application ID 0c7668b5-3260-4ad0-9f53-34ed54fa19b2.
Grant access-policy permissionsFor a key vault that uses access policies, grant Get, Wrap Key, and Unwrap Key.
Grant Azure RBAC permissionsFor a key vault that uses Azure RBAC, assign the Key Vault Crypto Service Encryption User role.
Wait for a scan cycleAllow up to 24 hours for the next scheduled scan.

AWS machines aren't scanned

DoneActionGuidance
Check the connectionConfirm that the AWS account appears as connected in Environment settings.
Check the settingConfirm that agentless scanning is turned on under Defender CSPM or Defender for Servers Plan 2.
Update connector permissionsDeploy the latest CloudFormation template and confirm that the deployment succeeds.
Check management-account deploymentFor an AWS management account, deploy the template as both a stack and a StackSet.
Wait for member connectorsAllow up to 24 hours for member-account connectors to be created.
Check the AMIAMIs that require third-party licensing, including applicable AWS Marketplace images, aren't supported.

GCP machines aren't scanned

DoneActionGuidance
Check the connectionConfirm that the GCP project or organization appears as connected in Environment settings.
Check the settingConfirm that agentless scanning is turned on under Defender CSPM or Defender for Servers Plan 2.
Update connector permissionsRun the current onboarding script at the intended GCP project or organization scope.
Check the organization policyConfirm that the policy for Compute Engine disks, images, and snapshots doesn't block Defender for Cloud.
Resolve a policy blockFollow Resolve an agentless scan error for GCP to update the organization policy.
Wait for a scan cycleAllow up to 24 hours for the next scheduled scan.

Results are missing or outdated for stopped machines

DoneActionGuidance
Start the machineAgentless scanning scans only machines that are running during the scheduled scan.
Wait for updated resultsKeep the machine running and allow up to 24 hours for results to update.

Malware scan has partial coverage

DoneActionGuidance
Check compressed package sizeA package larger than 1 GB can result in partial VM coverage.
Check the number of files in packagesA compressed package containing more than 10,000 files can result in partial coverage.
Check nested archivesMore than five nested archive levels can result in partial coverage.
Estimate the total eligible file countUse approximately 300,000 files for Windows and 500,000 files for Linux as planning targets, not enforced limits.
Review file-change volumeCreating or modifying approximately 200,000 files or more between scans can increase the risk of partial coverage.
Check file accessibilityEmpty, inaccessible, unavailable, system, offline, operating-system-level compressed, or reparse-point files might not be scanned.
Improve package coverageWhere operationally appropriate, reduce large file collections and extract or split packages that exceed the compressed-package thresholds.
Review available detectionsPartial coverage doesn't discard detections from content that was scanned successfully.

Malware alerts don't appear

DoneActionGuidance
Check the planDefender for Servers Plan 2 is required. Defender CSPM alone doesn't include malware scanning.
Check scanning eligibilityConfirm that agentless scanning is on and that the machine meets the support requirements.
Check other resultsVerify whether software inventory or vulnerability results appear for the machine.
Run a validation testMalware alerts appear only when a threat is detected. Follow Test agentless malware scanning to validate the feature.

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