Fiserv IP addresses Whitelisting in Cloudflare

Whitelisting IP Addresses in Cloudflare

Whitelisting (or allowlisting) IP addresses in Cloudflare helps ensure that trusted traffic—such as from partners, services, or your own systems—is never blocked by Cloudflare’s security features.

1. Log in to Cloudflare
   Go to your Cloudflare dashboard and select the website for which you want to whitelist an IP.

2. Navigate to Security Settings

   • Click on Security in the side menu.

   • Select WAF (Web Application Firewall).

3. Create a Custom Rule

   • Select Custom Rules.

   • Click on Create Rule.

4. Set Up the IP Whitelist Rule

   • In the rule builder, choose Field: Incoming IP Source.

   • Enter the IP address you wish to whitelist.

   • To add multiple IPs, use the OR operator between each IP address.

   • For the Action, select Skip (this tells Cloudflare to skip specific security checks for these IPs).

   • (Optional) Check the box to Skip all remaining custom rules for these IPs.

   • You may also want to skip certain protections, like Browser Integrity Check or User Agent Blocking, depending on your needs.

5. Deploy the Rule

   • Review the configuration, give your rule a descriptive name (e.g., “Allow Trusted IPs”), and click Deploy.

6. Verify Settings

   • Ensure the IP addresses are properly listed and the rule is active.

Best Practices and Notes

• If you’re whitelisting IP ranges, make sure you use CIDR notation (e.g., 192.0.2.0/24).

• Keep your list of whitelisted IP addresses up to date, especially if they belong to external vendors whose IPs might occasionally change.

• For advanced settings, you can also allowlist Cloudflare’s own IP ranges at your origin server to prevent accidental blocking of legitimate proxied traffic.

• Whitelisting too many IPs can reduce your site’s security, so use with caution.

Resources

• Cloudflare official documentation on IP access rules and custom firewall rules.

• Cloudflare’s current list of IP ranges (for reference when allowing Cloudflare traffic to your origin).

You can always modify, deactivate, or delete custom rules at any time through the Cloudflare dashboard. These instructions apply to the current Cloudflare interface as of August 2025 and are subject to minor interface changes in future updates.