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Event Information

  1. The dns.policies.create event in GCP for CloudDNS indicates that a new DNS policy has been created in the Cloud DNS service.
  2. This event signifies that a user or an automated process has defined a new policy to control how DNS queries are handled within the Cloud DNS service.
  3. The dns.policies.create event is important for tracking and auditing purposes, as it allows administrators to monitor the creation of DNS policies and ensure that the desired DNS configurations are being implemented.

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Examples

  1. Unauthorized creation of DNS policies: If security is impacted with dns.policies.create in GCP for CloudDNS, it could potentially allow unauthorized users to create DNS policies. This could lead to the creation of malicious policies that redirect traffic to unauthorized or malicious destinations, compromising the security and integrity of the DNS infrastructure.

  2. DNS hijacking: Another security impact of dns.policies.create in GCP for CloudDNS is the potential for DNS hijacking. Unauthorized creation of DNS policies could allow attackers to redirect DNS queries to malicious servers, leading to potential data exfiltration, phishing attacks, or other malicious activities.

  3. DNS cache poisoning: The creation of unauthorized DNS policies through dns.policies.create in GCP for CloudDNS can also lead to DNS cache poisoning. Attackers can manipulate DNS responses by creating policies that inject false DNS records into the cache, redirecting legitimate traffic to malicious destinations. This can result in users being directed to fake websites, leading to potential data theft or other security breaches.

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Remediation

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Using Console

To remediate the issues mentioned in the previous response for GCP CloudDNS using the GCP console, you can follow these step-by-step instructions:

  1. Enable DNSSEC for GCP CloudDNS:

    • Go to the GCP Console and navigate to the Cloud DNS page.
    • Select the DNS zone for which you want to enable DNSSEC.
    • Click on the “DNSSEC” tab.
    • Click on the “Enable DNSSEC” button.
    • Follow the instructions provided to complete the DNSSEC setup.

  2. Implement DNS logging and monitoring for GCP CloudDNS:

    • Go to the GCP Console and navigate to the Cloud DNS page.
    • Select the DNS zone for which you want to enable logging and monitoring.
    • Click on the “Logs” tab.
    • Click on the “Enable Logging” button.
    • Configure the desired log sink destination, such as Cloud Storage or BigQuery.
    • Click on the “Enable Monitoring” button.
    • Configure the desired monitoring settings, such as alerting policies.
    • Click on the “Save” button to apply the changes.

  3. Implement DNS query logging and analysis for GCP CloudDNS:

    • Go to the GCP Console and navigate to the Cloud DNS page.
    • Select the DNS zone for which you want to enable query logging and analysis.
    • Click on the “Logs” tab.
    • Click on the “Enable Query Logging” button.
    • Configure the desired log sink destination, such as Cloud Storage or BigQuery.
    • Click on the “Save” button to apply the changes.
    • Use tools like BigQuery or Data Studio to analyze the logged DNS queries and gain insights into your DNS traffic.

Note: The exact steps may vary slightly depending on the GCP Console interface and any updates made to the Cloud DNS service. It is always recommended to refer to the official GCP documentation for the most up-to-date instructions.

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Using CLI

To remediate the issues in GCP CloudDNS using GCP CLI, you can follow these steps:

  1. Ensure proper IAM permissions:

    • Grant the necessary IAM roles to the user or service account executing the CLI commands.
    • Use the gcloud projects add-iam-policy-binding command to add IAM roles to a project.

  2. Implement DNSSEC for CloudDNS:

    • Enable DNSSEC for a managed zone using the gcloud dns managed-zones update command with the --dnssec-state flag set to on.
    • Sign the zone using the gcloud dns dns-keys sign-zone command.

  3. Enable logging and monitoring for CloudDNS:

    • Enable query logging for a managed zone using the gcloud dns managed-zones update command with the --enable-query-logging flag set to true.
    • Create a log sink to export the logs to a desired destination using the gcloud logging sinks create command.
    • Enable monitoring and alerting for CloudDNS using the gcloud alpha monitoring policies create command to create a policy and gcloud alpha monitoring policies update command to update the policy.

Please note that the actual CLI commands may vary based on your specific requirements and configurations.

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Using Python

To remediate the issues mentioned in the previous response for GCP CloudDNS using Python, you can use the following approaches:

  1. Ensure DNSSEC is enabled:
    • Use the google-cloud-dns Python library to interact with the Cloud DNS API.
    • Use the dnssecConfig method to retrieve the current DNSSEC configuration for a specific managed zone.
    • If DNSSEC is not enabled, use the update method to enable DNSSEC for the managed zone.
from google.cloud import dns

def enable_dnssec(project_id, zone_name):
    client = dns.Client(project=project_id)
    zone = client.zone(zone_name)
    zone.fetch()
    
    if not zone.dnssec_config:
        zone.dnssec_config = dns.DnssecConfig(state=dns.DnssecState.ON)
        zone.update()
        print(f"DNSSEC enabled for zone: {zone_name}")
    else:
        print(f"DNSSEC is already enabled for zone: {zone_name}")
  1. Implement DNS logging:
    • Use the logging Python library to interact with the Cloud Logging API.
    • Create a log sink to export DNS logs to a destination of your choice (e.g., BigQuery, Cloud Storage, Pub/Sub).
    • Configure the log sink to filter DNS-related logs based on specific criteria (e.g., log severity, resource type).
    • Enable the log sink to start exporting DNS logs.
from google.cloud import logging_v2

def create_dns_log_sink(project_id, sink_name, destination_uri, filter_expr):
    client = logging_v2.LoggingServiceV2Client()
    parent = client.project_path(project_id)
    
    sink = {
        "name": sink_name,
        "destination": destination_uri,
        "filter": filter_expr,
        "output_version_format": "V2",
    }
    
    response = client.create_sink(parent, sink)
    print(f"DNS log sink created: {response.name}")
  1. Monitor DNS changes with Cloud Monitoring:
    • Use the google-cloud-monitoring Python library to interact with the Cloud Monitoring API.
    • Create a metric descriptor to define a custom metric for DNS changes.
    • Create a metric time series to record the DNS changes using the custom metric descriptor.
    • Set up an alerting policy to trigger notifications based on specific conditions related to DNS changes.
from google.cloud import monitoring_v3

def create_dns_change_metric(project_id, metric_type, metric_kind, value_type):
    client = monitoring_v3.MetricServiceClient()
    project_name = client.project_path(project_id)
    
    descriptor = {
        "type": metric_type,
        "metric_kind": metric_kind,
        "value_type": value_type,
        "labels": [
            {
                "key": "zone",
                "value_type": "STRING",
                "description": "Managed zone name"
            }
        ]
    }
    
    response = client.create_metric_descriptor(project_name, descriptor)
    print(f"DNS change metric created: {response.name}")

Please note that the provided Python scripts are just examples and may require additional modifications based on your specific requirements and environment setup.