​
Event Information

  • The Microsoft.Compute.virtualMachines.restart.action event in Azure for AzureVirtualMachines refers to an event where a virtual machine is being restarted.
  • This event is triggered when an explicit restart action is initiated on the virtual machine, either manually or through an automated process.
  • The restart action can be performed for various reasons, such as applying updates, resolving performance issues, or troubleshooting the virtual machine.

​
Examples

  1. Unauthorized access: If security is impacted with Microsoft.Compute.virtualMachines.restart.action, it could potentially allow unauthorized access to the virtual machine. This action may restart the virtual machine, but if proper access controls are not in place, it could allow an attacker to gain access to sensitive data or resources within the virtual machine.

  2. Denial of Service (DoS): Restarting a virtual machine can be used as a technique to disrupt the availability of a service. If an attacker gains access to the restart action, they could repeatedly restart the virtual machine, causing a denial of service for legitimate users or applications relying on that virtual machine.

  3. Exploitation of vulnerabilities: Restarting a virtual machine may trigger certain vulnerabilities that exist within the operating system or applications running on it. If these vulnerabilities are not properly patched or mitigated, an attacker could exploit them during the restart process, potentially gaining unauthorized access or causing further security issues within the virtual machine.

​
Remediation

​
Using Console

To remediate the issues for Azure Virtual Machines using the Azure console, you can follow these step-by-step instructions:

  1. Enable Azure Security Center:

    • Go to the Azure portal and search for “Security Center” in the search bar.
    • Select “Security Center” from the results and click on it.
    • In the Security Center dashboard, click on “Pricing & settings” in the left menu.
    • Choose the subscription and resource group where your Azure Virtual Machines are located.
    • Click on “Apply to all resources” to enable Security Center for all resources in the selected subscription and resource group.
    • Review the pricing tier options and select the appropriate tier for your needs.
    • Click on “Save” to enable Security Center.

  2. Implement Network Security Groups (NSGs):

    • Go to the Azure portal and search for “Virtual machines” in the search bar.
    • Select “Virtual machines” from the results and click on it.
    • Choose the virtual machine you want to secure with NSGs.
    • In the virtual machine’s overview page, click on “Networking” in the left menu.
    • Under “Inbound port rules” and “Outbound port rules”, click on “Add inbound port rule” and “Add outbound port rule” respectively.
    • Configure the necessary rules to allow only the required inbound and outbound traffic.
    • Click on “Save” to apply the NSG rules to the virtual machine.

  3. Implement Azure Backup:

    • Go to the Azure portal and search for “Recovery Services vaults” in the search bar.
    • Select “Recovery Services vaults” from the results and click on it.
    • Click on “Add” to create a new Recovery Services vault.
    • Provide the necessary details like subscription, resource group, and vault name.
    • Choose the appropriate region for the vault.
    • Click on “Review + create” and then “Create” to create the vault.
    • Once the vault is created, go to the virtual machine’s overview page.
    • Click on “Backup” in the left menu.
    • Click on “Backup now” to initiate an immediate backup of the virtual machine.
    • Configure the backup settings as per your requirements.
    • Click on “Enable backup” to start the backup process.

Note: These instructions provide a general overview of the steps involved in remediating the mentioned issues. It is recommended to refer to the official Azure documentation for detailed instructions and best practices.

​
Using CLI

To remediate the issues for Azure Virtual Machines using Azure CLI, you can follow these steps:

  1. Enable Azure Security Center for Azure Virtual Machines:

    • Use the Azure CLI command az vm update --name <vm_name> --resource-group <resource_group_name> --set "properties.securityProfile.securityCenterEnabled=true" to enable Azure Security Center for a specific virtual machine.

  2. Configure Network Security Groups (NSGs) for Azure Virtual Machines:

    • Use the Azure CLI command az network nsg rule create --name <rule_name> --nsg-name <nsg_name> --resource-group <resource_group_name> --priority <priority_number> --source-address-prefixes <source_address_prefix> --destination-port-ranges <destination_port_range> --access <access_type> --protocol <protocol> to create a new NSG rule for a specific NSG and virtual machine.

  3. Implement Azure Backup for Azure Virtual Machines:

    • Use the Azure CLI command az backup protection enable-for-vm --vm <vm_name> --vault-name <vault_name> --resource-group <resource_group_name> --policy-name <policy_name> to enable Azure Backup protection for a specific virtual machine. Replace the placeholders with the appropriate values for your environment.

Please note that the actual CLI commands may vary depending on your specific requirements and configurations. Make sure to replace the placeholders with the actual values relevant to your Azure environment.

​
Using Python

To remediate the issues for Azure Virtual Machines using Python, you can use the Azure SDK for Python. Here are three examples of how you can remediate common issues:

  1. Example 1: Start a stopped virtual machine
from azure.identity import DefaultAzureCredential
from azure.mgmt.compute import ComputeManagementClient

# Authenticate using default credentials
credential = DefaultAzureCredential()

# Create a ComputeManagementClient
compute_client = ComputeManagementClient(credential, subscription_id)

# Specify the resource group and virtual machine name
resource_group_name = "your_resource_group_name"
vm_name = "your_vm_name"

# Start the virtual machine
compute_client.virtual_machines.start(resource_group_name, vm_name)
  1. Example 2: Resize a virtual machine
from azure.identity import DefaultAzureCredential
from azure.mgmt.compute import ComputeManagementClient

# Authenticate using default credentials
credential = DefaultAzureCredential()

# Create a ComputeManagementClient
compute_client = ComputeManagementClient(credential, subscription_id)

# Specify the resource group and virtual machine name
resource_group_name = "your_resource_group_name"
vm_name = "your_vm_name"

# Specify the new size for the virtual machine
new_vm_size = "Standard_DS2_v2"

# Resize the virtual machine
compute_client.virtual_machines.begin_update(resource_group_name, vm_name, {"hardware_profile": {"vm_size": new_vm_size}})
  1. Example 3: Restart a virtual machine
from azure.identity import DefaultAzureCredential
from azure.mgmt.compute import ComputeManagementClient

# Authenticate using default credentials
credential = DefaultAzureCredential()

# Create a ComputeManagementClient
compute_client = ComputeManagementClient(credential, subscription_id)

# Specify the resource group and virtual machine name
resource_group_name = "your_resource_group_name"
vm_name = "your_vm_name"

# Restart the virtual machine
compute_client.virtual_machines.restart(resource_group_name, vm_name)

Please note that you need to install the required Azure SDK for Python packages (azure-identity and azure-mgmt-compute) before running these scripts.