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More Info:

Ensure that “Restrict VM IP Forwarding” policy is enforced at the GCP organization level.

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Risk Level

Medium

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Address

Security, Operational Maturity

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Compliance Standards

CISGCP, CBP

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Remediation

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Using Console

To remediate the misconfiguration “Restrict Virtual Machine IP Forwarding” in GCP using the GCP console, you can follow the below steps:

  1. Login to the GCP console with your credentials.

  2. Navigate to the Compute Engine section from the left-hand side menu.

  3. Click on the “VM instances” option in the submenu.

  4. Select the virtual machine instance for which you want to restrict IP forwarding.

  5. Click on the “Edit” button at the top of the page.

  6. Scroll down to the “Network interfaces” section and click on the “Edit” button for the relevant network interface.

  7. In the “IP forwarding” section, select the “Off” option.

  8. Click on the “Save” button to apply the changes.

  9. Repeat the above steps for all the virtual machine instances in your GCP account.

By following the above steps, you can remediate the misconfiguration “Restrict Virtual Machine IP Forwarding” in GCP using the GCP console.

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Using CLI

To remediate the “Restrict Virtual Machine IP Forwarding” misconfiguration in GCP using GCP CLI, you can follow the below steps:

Step 1: Open the Cloud Shell from the GCP console.

Step 2: Run the following command to list all the virtual machines in the project:

gcloud compute instances list

Step 3: Identify the virtual machine for which you want to restrict IP forwarding.

Step 4: Run the following command to update the virtual machine configuration and restrict IP forwarding:

gcloud compute instances update [VM_NAME] --no-enable-ip-forwarding

Replace [VM_NAME] with the name of the virtual machine identified in Step 3.

Step 5: Verify that IP forwarding is disabled for the virtual machine by running the following command:

gcloud compute instances describe [VM_NAME] | grep -i "can ip forward"

The output should show “canIpForward: false”.

By following these steps, you can remediate the “Restrict Virtual Machine IP Forwarding” misconfiguration in GCP using GCP CLI.

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Using Python

To remediate the misconfiguration of “Restrict Virtual Machine IP Forwarding” for GCP using Python, you can follow these steps:

  1. Import the necessary GCP library:
from google.cloud import compute_v1
  1. Set up the client object:
client = compute_v1.InstancesClient()
  1. Get the instance resource:
instance = client.get('your-project', 'your-zone', 'your-instance')
  1. Update the instance configuration to restrict IP forwarding:
instance.can_ip_forward = False
update_mask = ['can_ip_forward']
client.update(instance=instance, update_mask=update_mask)
  1. Verify that the IP forwarding is restricted:
updated_instance = client.get('your-project', 'your-zone', 'your-instance')
if updated_instance.can_ip_forward == False:
    print('IP forwarding has been restricted.')

By following these steps, you can remediate the misconfiguration of “Restrict Virtual Machine IP Forwarding” for GCP using Python.