Microsoft AzureOverview
Only install organization-approved extensions on VMs.
Cyscale lists all VMs with any extension installed. Please review them and exempt the VMs with approved extensions.
Rationale
Azure virtual machine extensions are small applications that provide post-deployment configuration and automation tasks on Azure virtual machines. These extensions run with administrative privileges and can access anything on a virtual machine. The Azure Portal and community provide several such extensions. Each organization should carefully evaluate these extensions and ensure that only those approved for use are implemented.
Remediation guidance
From Azure Console
- Open the VM using the
Open in Azurebutton - Go to
Settings - Click on
Extensions - If there are unapproved extensions, uninstall them.
From Azure Command Line Interface
List the installed extensions for the VM:
az vm extension list --vm-name <vmName> --resource-group <resourceGroupName> --query [*].name
Delete the extensions that are not approved:
az vm extension delete --resource-group <resourceGroupName> --vm-name <vmName> --name <extensionName>
Default Value
By default, no extensions are added to the virtual machines.
References
- https://learn.microsoft.com/en-us/azure/virtual-machines/windows/extensions-features
- https://learn.microsoft.com/en-us/azure/security/benchmarks/security-controls-v2-endpoint-security
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
- Fix the baseline first at the account, subscription, project, cluster, or tenant scope that owns this control.
- Remediate the currently affected resources in batches, starting with internet-exposed and production assets.
- Re-scan and track approved exceptions with an owner and expiry date.
Query logic
These are the stored checks tied to this control.
Azure VMs with extensions
Connectors
Covered asset types
Expected check: eq []
{
vms(where: { NOT: { extensions_SOME: null } }) {
...AssetFragment
}
}
