Collect CrowdStrike FileVantage logs

Supported in:

Google secops SIEM

Note: This feature is covered by Pre-GA Offerings Terms of the Google Security Operations Service Specific Terms. Pre-GA features might have limited support, and changes to pre-GA features might not be compatible with other pre-GA versions. For more information, see the Google SecOps Technical Support Service guidelines and the Google SecOps Service Specific Terms.

This document explains how to ingest CrowdStrike FileVantage logs to Google Security Operations using Google Cloud Storage. CrowdStrike FileVantage is a file integrity monitoring solution that tracks changes to critical files and directories across your environment.

Before you begin

Ensure that you have the following prerequisites:

• A Google SecOps instance
• A GCP project with Cloud Storage API enabled
• Permissions to create and manage GCS buckets
• Permissions to manage IAM policies on GCS buckets
• Permissions to create Cloud Run services, Pub/Sub topics, and Cloud Scheduler jobs

• Privileged access to CrowdStrike Falcon Console

  Note: The CrowdStrike FileVantage API endpoints and scopes described in this guide are documented in the CrowdStrike Falcon API. Access to the full API documentation requires a CrowdStrike customer or partner account. Contact CrowdStrike support if you need assistance with API access.

Create Google Cloud Storage bucket

1. Go to the Google Cloud Console.
2. Select your project or create a new one.
3. In the navigation menu, go to Cloud Storage > Buckets.
4. Click Create bucket.

5. Provide the following configuration details:

   Setting	Value
   Name your bucket	Enter a globally unique name (for example, crowdstrike-filevantage-logs)
   Location type	Choose based on your needs (Region, Dual-region, Multi-region)
   Location	Select the location (for example, us-central1)
   Storage class	Standard (recommended for frequently accessed logs)
   Access control	Uniform (recommended)
   Protection tools	Optional: Enable object versioning or retention policy

6. Click Create.

Collect CrowdStrike FileVantage API credentials

1. Sign in to the CrowdStrike Falcon Console.
2. Go to Support and resources > API clients and keys.
3. Click Add new API client.
4. Provide the following configuration details:
   • Client name: Enter a descriptive name (for example, Google SecOps FileVantage Integration).
   • Description: Enter a brief description of the integration purpose.
   • API scopes: Select Falcon FileVantage:read.
5. Click Add to complete the process.

6. Copy and save in a secure location the following details:

   • Client ID
   • Client Secret
   • Base URL (determines your cloud region)
   Note: The user account must have CrowdStrike Falcon Administrator role to create API clients.

Verify permissions

To verify the account has the required permissions:

1. Sign in to the CrowdStrike Falcon Console.
2. Go to Support and resources > API clients and keys.
3. If you can see the API clients and keys page and create new API clients, you have the required permissions.
4. If you cannot access this page, contact your CrowdStrike administrator to grant Falcon Administrator role.

Test API access

• Test your credentials before proceeding with the integration:

  # Replace with your actual credentials
  FALCON_CLIENT_ID="your-client-id"
  FALCON_CLIENT_SECRET="your-client-secret"
  FALCON_BASE_URL="https://api.crowdstrike.com"
  
  # Get OAuth token
  TOKEN=$(curl -s -X POST "${FALCON_BASE_URL}/oauth2/token" \
    -H "Content-Type: application/x-www-form-urlencoded" \
    -d "client_id=${FALCON_CLIENT_ID}&client_secret=${FALCON_CLIENT_SECRET}&grant_type=client_credentials" \
    | grep -o '"access_token":"[^"]*' | cut -d'"' -f4)
  
  # Test FileVantage API access
  curl -v -H "Authorization: Bearer ${TOKEN}" \
    "${FALCON_BASE_URL}/filevantage/queries/changes/v3?limit=1"
  

Create service account for Cloud Run function

The Cloud Run function needs a service account with permissions to write to GCS bucket and be invoked by Pub/Sub.

Create service account

1. In the GCP Console, go to IAM & Admin > Service Accounts.
2. Click Create Service Account.
3. Provide the following configuration details:
   • Service account name: Enter crowdstrike-filevantage-sa.
   • Service account description: Enter Service account for Cloud Run function to collect CrowdStrike FileVantage logs.
4. Click Create and Continue.
5. In the Grant this service account access to project section, add the following roles:
   1. Click Select a role.
   2. Search for and select Storage Object Admin.
   3. Click + Add another role.
   4. Search for and select Cloud Run Invoker.
   5. Click + Add another role.
   6. Search for and select Cloud Functions Invoker.
6. Click Continue.
7. Click Done.

These roles are required for:

• Storage Object Admin: Write logs to GCS bucket and manage state files
• Cloud Run Invoker: Allow Pub/Sub to invoke the function
• Cloud Functions Invoker: Allow function invocation

Grant IAM permissions on GCS bucket

Grant the service account write permissions on the GCS bucket:

1. Go to Cloud Storage > Buckets.
2. Click your bucket name (for example, crowdstrike-filevantage-logs).
3. Go to the Permissions tab.
4. Click Grant access.
5. Provide the following configuration details:
   • Add principals: Enter the service account email (for example, crowdstrike-filevantage-sa@PROJECT_ID.iam.gserviceaccount.com).
   • Assign roles: Select Storage Object Admin.
6. Click Save.

Create Pub/Sub topic

Create a Pub/Sub topic that Cloud Scheduler will publish to and the Cloud Run function will subscribe to.

1. In the GCP Console, go to Pub/Sub > Topics.
2. Click Create topic.
3. Provide the following configuration details:
   • Topic ID: Enter crowdstrike-filevantage-trigger.
   • Leave other settings as default.
4. Click Create.

Create Cloud Run function to collect logs

The Cloud Run function is triggered by Pub/Sub messages from Cloud Scheduler to fetch logs from CrowdStrike FileVantage API and writes them to GCS.

1. In the GCP Console, go to Cloud Run.
2. Click Create service.
3. Select Function (use an inline editor to create a function).

4. In the Configure section, provide the following configuration details:

   Setting	Value
   Service name	crowdstrike-filevantage-collector
   Region	Select region matching your GCS bucket (for example, us-central1)
   Runtime	Select Python 3.12 or later

5. In the Trigger (optional) section:

   1. Click + Add trigger.
   2. Select Cloud Pub/Sub.
   3. In Select a Cloud Pub/Sub topic, choose the Pub/Sub topic (crowdstrike-filevantage-trigger).
   4. Click Save.

6. In the Authentication section:

   1. Select Require authentication.
   2. Check Identity and Access Management (IAM).
   Note: Pub/Sub automatically handles authentication when invoking the function.

7. Scroll down and expand Containers, Networking, Security.

8. Go to the Security tab:

   • Service account: Select the service account (crowdstrike-filevantage-sa).

9. Go to the Containers tab:

   1. Click Variables & Secrets.
   2. Click + Add variable for each environment variable:

   Variable Name	Example Value
   GCS_BUCKET	crowdstrike-filevantage-logs
   GCS_PREFIX	filevantage/
   STATE_KEY	filevantage/state.json
   FALCON_CLIENT_ID	your-client-id
   FALCON_CLIENT_SECRET	your-client-secret
   FALCON_BASE_URL	https://api.crowdstrike.com (US-1) / https://api.us-2.crowdstrike.com (US-2) / https://api.eu-1.crowdstrike.com (EU-1)

10. In the Variables & Secrets section, scroll down to Requests:

    • Request timeout: Enter 600 seconds (10 minutes).

11. Go to the Settings tab:

    • In the Resources section:
      • Memory: Select 512 MiB or higher.
      • CPU: Select 1.

12. In the Revision scaling section:

    • Minimum number of instances: Enter 0.
    • Maximum number of instances: Enter 100 (or adjust based on expected load).

13. Click Create.

14. Wait for the service to be created (1-2 minutes).

15. After the service is created, the inline code editor opens automatically.

Add function code

1. Enter main in Function entry point

2. In the inline code editor, create two files:

   • First file: main.py:

   import functions_framework
   from google.cloud import storage
   import json
   import os
   import urllib3
   from datetime import datetime, timezone, timedelta
   import time
   
   # Initialize HTTP client with timeouts
   http = urllib3.PoolManager(
       timeout=urllib3.Timeout(connect=5.0, read=30.0),
       retries=False,
   )
   
   # Initialize Storage client
   storage_client = storage.Client()
   
   @functions_framework.cloud_event
   def main(cloud_event):
       """
       Cloud Run function triggered by Pub/Sub to fetch CrowdStrike FileVantage logs and write to GCS.
   
       Args:
           cloud_event: CloudEvent object containing Pub/Sub message
       """
   
       # Get environment variables
       bucket_name = os.environ.get('GCS_BUCKET')
       prefix = os.environ.get('GCS_PREFIX', 'filevantage/')
       state_key = os.environ.get('STATE_KEY', 'filevantage/state.json')
       client_id = os.environ.get('FALCON_CLIENT_ID')
       client_secret = os.environ.get('FALCON_CLIENT_SECRET')
       base_url = os.environ.get('FALCON_BASE_URL')
   
       if not all([bucket_name, client_id, client_secret, base_url]):
           print('Error: Missing required environment variables')
           return
   
       try:
           # Get GCS bucket
           bucket = storage_client.bucket(bucket_name)
   
           # Get OAuth token
           token_url = f"{base_url}/oauth2/token"
           token_headers = {
               'Content-Type': 'application/x-www-form-urlencoded',
               'Accept': 'application/json'
           }
           token_data = f"client_id={client_id}&client_secret={client_secret}&grant_type=client_credentials"
   
           token_response = http.request(
               'POST',
               token_url,
               body=token_data.encode('utf-8'),
               headers=token_headers
           )
   
           if token_response.status != 200:
               print(f"Failed to get OAuth token: {token_response.status}")
               print(f"Response: {token_response.data.decode('utf-8')}")
               return
   
           token_data_json = json.loads(token_response.data.decode('utf-8'))
           access_token = token_data_json['access_token']
   
           # Get last checkpoint
           last_timestamp = get_last_checkpoint(bucket, state_key)
   
           # Fetch file changes using v3 endpoint (high volume query)
           changes_url = f"{base_url}/filevantage/queries/changes/v3"
           headers = {
               'Authorization': f'Bearer {access_token}',
               'Accept': 'application/json'
           }
   
           # Build query parameters
           params = []
           params.append('limit=5000')
           params.append('sort=action_timestamp|asc')
   
           if last_timestamp:
               params.append(f"filter=action_timestamp:>'{last_timestamp}'")
   
           query_url = f"{changes_url}?{'&'.join(params)}"
   
           backoff = 1.0
           max_retries = 3
   
           for attempt in range(max_retries):
               response = http.request('GET', query_url, headers=headers)
   
               if response.status == 429:
                   retry_after = int(response.headers.get('Retry-After', str(int(backoff))))
                   print(f"Rate limited (429). Retrying after {retry_after}s...")
                   time.sleep(retry_after)
                   backoff = min(backoff * 2, 30.0)
                   continue
   
               if response.status != 200:
                   print(f"Failed to query changes: {response.status}")
                   print(f"Response: {response.data.decode('utf-8')}")
                   return
   
               break
           else:
               print("Max retries exceeded")
               return
   
           response_data = json.loads(response.data.decode('utf-8'))
           change_ids = response_data.get('resources', [])
   
           if not change_ids:
               print("No new changes found")
               return
   
           # Get detailed change information using v2 endpoint
           details_url = f"{base_url}/filevantage/entities/changes/v2"
           batch_size = 500
           all_changes = []
           latest_timestamp = last_timestamp
   
           for i in range(0, len(change_ids), batch_size):
               batch_ids = change_ids[i:i + batch_size]
   
               # Build query string with multiple ids parameters
               ids_params = '&'.join([f'ids={id}' for id in batch_ids])
               details_query_url = f"{details_url}?{ids_params}"
   
               backoff = 1.0
               for attempt in range(max_retries):
                   details_response = http.request('GET', details_query_url, headers=headers)
   
                   if details_response.status == 429:
                       retry_after = int(details_response.headers.get('Retry-After', str(int(backoff))))
                       print(f"Rate limited (429). Retrying after {retry_after}s...")
                       time.sleep(retry_after)
                       backoff = min(backoff * 2, 30.0)
                       continue
   
                   if details_response.status == 200:
                       details_data = json.loads(details_response.data.decode('utf-8'))
                       changes = details_data.get('resources', [])
                       all_changes.extend(changes)
   
                       # Track latest timestamp
                       for change in changes:
                           change_time = change.get('action_timestamp')
                           if change_time and (not latest_timestamp or change_time > latest_timestamp):
                               latest_timestamp = change_time
                       break
                   else:
                       print(f"Failed to get change details (batch {i//batch_size + 1}): {details_response.status}")
                       break
   
           if all_changes:
               # Store logs in GCS
               timestamp = datetime.now(timezone.utc).strftime('%Y%m%d_%H%M%S')
               blob_name = f"{prefix}filevantage_changes_{timestamp}.json"
               blob = bucket.blob(blob_name)
               log_lines = '\n'.join(json.dumps(change) for change in all_changes)
               blob.upload_from_string(log_lines, content_type='application/json')
   
               # Update checkpoint
               save_checkpoint(bucket, state_key, latest_timestamp)
   
               print(f"Stored {len(all_changes)} changes in GCS: {blob_name}")
   
       except Exception as e:
           print(f"Error: {str(e)}")
           raise
   
   def get_last_checkpoint(bucket, key):
       """Get the last processed timestamp from GCS state file"""
       try:
           blob = bucket.blob(key)
           if blob.exists():
               state_data = blob.download_as_text()
               state = json.loads(state_data)
               return state.get('last_timestamp')
       except Exception as e:
           print(f"Error reading checkpoint: {e}")
       return None
   
   def save_checkpoint(bucket, key, timestamp):
       """Save the last processed timestamp to GCS state file"""
       try:
           state = {
               'last_timestamp': timestamp,
               'updated_at': datetime.now(timezone.utc).isoformat()
           }
           blob = bucket.blob(key)
           blob.upload_from_string(
               json.dumps(state),
               content_type='application/json'
           )
       except Exception as e:
           print(f"Error saving checkpoint: {e}")
   

   • Second file: requirements.txt:

   functions-framework==3.*
   google-cloud-storage==2.*
   urllib3>=2.0.0
   

3. Click Deploy to save and deploy the function.

4. Wait for deployment to complete (2-3 minutes).

   Note: The Pub/Sub trigger configuration automatically creates the necessary subscriptions and permissions.

Create Cloud Scheduler job

Cloud Scheduler publishes messages to the Pub/Sub topic at regular intervals, triggering the Cloud Run function.

1. In the GCP Console, go to Cloud Scheduler.
2. Click Create Job.

3. Provide the following configuration details:

   Setting	Value
   Name	crowdstrike-filevantage-hourly
   Region	Select same region as Cloud Run function
   Frequency	*/15 * * * * (every 15 minutes)
   Timezone	Select timezone (UTC recommended)
   Target type	Pub/Sub
   Topic	Select the Pub/Sub topic (crowdstrike-filevantage-trigger)
   Message body	{} (empty JSON object)

4. Click Create.

   Note: A 15-minute polling interval is recommended to avoid hitting rate limits while maintaining reasonable data freshness. Adjust based on your log volume and latency requirements.

Test the scheduler job

1. In the Cloud Scheduler console, find your job (crowdstrike-filevantage-hourly).
2. Click Force run to trigger manually.
3. Wait a few seconds and go to Cloud Run > Services > crowdstrike-filevantage-collector > Logs.
4. Verify the function executed successfully.
5. Check the GCS bucket (crowdstrike-filevantage-logs) to confirm logs were written.

Retrieve the Google SecOps service account

Google SecOps uses a unique service account to read data from your GCS bucket. You must grant this service account access to your bucket.

Get the service account email

1. Go to SIEM Settings > Feeds.
2. Click Add New Feed.
3. Click Configure a single feed.
4. In the Feed name field, enter a name for the feed (for example, CrowdStrike FileVantage logs).
5. Select Google Cloud Storage V2 as the Source type.
6. Select CrowdStrike Filevantage as the Log type.

7. Click Get Service Account. A unique service account email is displayed, for example:

   [e-mail]
   

8. Copy this email address for use in the next step.

   Note: Each Google SecOps instance has a unique service account. Don't use service accounts from other documentation or examples.

Grant IAM permissions to the Google SecOps service account

The Google SecOps service account needs Storage Object Viewer role on your GCS bucket.

1. Go to Cloud Storage > Buckets.
2. Click your bucket name (for example, crowdstrike-filevantage-logs).
3. Go to the Permissions tab.
4. Click Grant access.
5. Provide the following configuration details:
   • Add principals: Paste the Google SecOps service account email.
   • Assign roles: Select Storage Object Viewer.

6. Click Save.

   Note: If you plan to use the deletion option "Delete transferred files" or "Delete transferred files and empty directories," grant Storage Object Admin role instead of Storage Object Viewer.

Configure a feed in Google SecOps to ingest CrowdStrike FileVantage logs

1. Go to SIEM Settings > Feeds.
2. Click Add New Feed.
3. Click Configure a single feed.
4. In the Feed name field, enter a name for the feed (for example, CrowdStrike FileVantage logs).
5. Select Google Cloud Storage V2 as the Source type.
6. Select CrowdStrike Filevantage as the Log type.
7. Click Next.

8. Specify values for the following input parameters:

   • Storage bucket URL: Enter the GCS bucket URI with the prefix path:

     gs://crowdstrike-filevantage-logs/filevantage/
     

     • Replace:

       • crowdstrike-filevantage-logs: Your GCS bucket name.
       • filevantage/: Prefix/folder path where logs are stored.
     Note: Always include the trailing slash (/) at the end of the URI.

   • Source deletion option: Select the deletion option according to your preference:

     • Never: Never deletes any files after transfers (recommended for testing).
     • Delete transferred files: Deletes files after successful transfer.

     • Delete transferred files and empty directories: Deletes files and empty directories after successful transfer.

       Note: If you select a deletion option, the service account must have Storage Object Admin role instead of Storage Object Viewer. Update IAM permissions accordingly.

   • Maximum File Age: Include files modified in the last number of days. Default is 180 days.

   • Asset namespace: The asset namespace.

   • Ingestion labels: The label to be applied to the events from this feed.

9. Click Next.

10. Review your new feed configuration in the Finalize screen, and then click Submit.

Need more help? Get answers from Community members and Google SecOps professionals.