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Event Information

  • The Microsoft.ClassicCompute.virtualMachines.write event in Azure for AzureVirtualMachines refers to a write operation performed on a virtual machine (VM) resource in the Classic deployment model.
  • This event indicates that a change or modification has been made to the configuration or properties of a VM in the Classic deployment model.
  • It could involve actions such as creating a new VM, updating the VM’s size or settings, or deleting the VM from the Classic deployment model.

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Examples

  1. Unauthorized creation of virtual machines: If security is impacted with Microsoft.ClassicCompute.virtualMachines.write permission, it means that users or applications with this permission can create virtual machines in the Azure Classic deployment model. This can lead to unauthorized creation of virtual machines, potentially allowing malicious actors to gain access to sensitive data or resources within the virtual machine.

  2. Misconfiguration of virtual machines: With the ability to write to AzureVirtualMachines, there is a risk of misconfiguration of virtual machines. This can include insecure network settings, weak access controls, or improper storage configurations, which can expose the virtual machine to security vulnerabilities and increase the risk of unauthorized access or data breaches.

  3. Unauthorized modification of virtual machines: The Microsoft.ClassicCompute.virtualMachines.write permission also allows users to modify existing virtual machines. If security is impacted, it means that unauthorized modifications can be made to virtual machines, potentially compromising their integrity or introducing malicious code. This can result in unauthorized access, data loss, or disruption of services running on the virtual machine.

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Remediation

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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 that you want to secure with NSGs.
    • In the virtual machine’s overview page, click on “Networking” in the left menu.
    • Under “Inbound port rules”, click on “Add inbound port rule” to define the allowed inbound traffic.
    • Specify the necessary details such as source IP address, destination port, and protocol.
    • Repeat the above step to add additional inbound port rules as needed.
    • 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.
    • Specify the necessary details such as subscription, resource group, and vault name.
    • Choose the appropriate storage replication option and click on “Review + create”.
    • Review the settings and click on “Create” to create the Recovery Services vault.
    • Once the vault is created, go to the virtual machine’s overview page.
    • Click on “Backup” in the left menu and then click on “Backup now” to initiate a backup job.
    • Follow the prompts to configure the backup settings and schedule.
    • Click on “OK” to start the backup job.

These steps will help you remediate the mentioned issues for Azure Virtual Machines using the Azure console.

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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 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.

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Using Python

To remediate the issues for Azure Virtual Machines using Python, you can use the following approaches:

  1. Automate VM deployment and configuration:

    • Use the Azure SDK for Python to programmatically create and configure virtual machines.
    • Write a Python script that leverages the Azure Management Libraries to automate the deployment process.
    • Use the azure-mgmt-compute library to create virtual machines with the desired configurations, such as specifying the VM size, OS image, and network settings.

  2. Implement monitoring and alerting:

    • Use the Azure Monitor service to set up alerts for specific events or conditions on your virtual machines.
    • Write a Python script that utilizes the Azure Monitor API to create and manage alerts.
    • Configure the alerts to trigger actions, such as sending notifications or executing remediation scripts, when certain thresholds or conditions are met.

  3. Implement security best practices:

    • Use the Azure Security Center to monitor and assess the security posture of your virtual machines.
    • Write a Python script that interacts with the Azure Security Center API to retrieve security recommendations and implement them.
    • Implement security measures such as enabling disk encryption, configuring network security groups, and applying access control policies using the azure-mgmt-security library.

Please note that the provided examples are high-level guidelines, and the actual implementation may vary based on your specific requirements and the Azure services you are using.