Recommended DNS policies
3 min read
We recommend you add the following DNS policies to build an Internet and SaaS app security strategy for your organization. Allowlist any known domains and hostnames. With this policy, you ensure that your users can access your organization’s domains even if the domains fall under a blocked category, such as Newly Seen Domains or Login Screens. Restrict access for users included in an identity provider (IdP) user group for risky users. This policy ensures your security team can restrict traffic for users of whom malicious or suspicious activity was detected. Block security categories, such as Command and Control & Botnet and Malware, based on Cloudflare’s threat intelligence. Entries in the security risk content subcategory, such as New Domains, do not always pose a security threat. We recommend you first create an Allow policy to track policy matching and identify any false positives. You can add false positives to your Trusted Domains list used in All-DNS-Domain-Allowlist. After your test is complete, we recommend you change the action to Block to minimize risk to your organization. Block unauthorized applications to limit your users’ access to certain web-based tools and minimize the risk of shadow IT. For example, the following policy blocks popular AI chatbots. Block websites hosted in countries categorized as high risk. The designation of such countries may result from your organization’s users or through the implementation of regulations including EAR, OFAC, and ITAR. Block frequently misused top-level domains (TLDs) to reduce security risks, especially when there is no discernible advantage to be gained from allowing access. Similarly, restricting access to specific country-level TLDs may be necessary to comply with regulations such as OFAC and ITAR. Block misused domains to protect your users against sophisticated phishing attacks, such as domains that specifically target your organization. For example, the following policy blocks specific keywords associated with an organization or its authentication services (such as Block specific IP addresses that are malicious or pose a threat to your organization. You can implement this policy by either creating custom blocklists or by using blocklists provided by threat intelligence partners or regional Computer Emergency and Response Teams (CERTs). Ideally, your CERTs can update the blocklist with an API automation to provide real-time threat protection. Block specific domains or hosts that are malicious or pose a threat to your organization. Like All-DNS-ResolvedIP-Blocklist, this blocklist can be updated manually or via API automation.All-DNS-Domain-Allowlist
Selector Operator Value Logic Action Domain in list Known Domains Or Allow Host in list Known Domains Quarantined-Users-DNS-Restricted-Access
Selector Operator Value Logic Action Domain in list Known Domains Or Block Host in list Known Domains And User Group Names in Quarantined Users All-DNS-SecurityCategories-Blocklist
Selector Operator Value Action Security Categories in All security risks Block All-DNS-ContentCategories-Blocklist
Selector Operator Value Action Content Categories in Security Risks Allow All-DNS-Application-Blocklist
Selector Operator Value Action Application in ChatGPT, Bard Block All-DNS-GeoCountryIP-Blocklist
Selector Operator Value Action Resolved Country IP Geolocation in Afghanistan, Belarus, Congo (Kinshasa), Cuba, Iran, Iraq, Korea (North), Myanmar, Russian Federation, Sudan, Syria, Ukraine, Zimbabwe Block All-DNS-DomainTopLevel-Blocklist
Selector Operator Value Action Domain matches regex [.](cn|ru)$ or [.](rest|hair|top|live|cfd|boats|beauty|mom|skin|okinawa)$ or [.](zip|mobi)$Block All-DNS-DomainPhishing-Blocklist
okta, 2fa, cloudflare and sso) while still allowing access to known domains.Selector Operator Value Logic Action Domain not in list Known Domains And Block Domain matches regex .*okta.*|.*cloudflare.*|.*mfa.*|.sso.*All-DNS-ResolvedIP-Blocklist
Selector Operator Value Action Resolved IP in list IP Blocklist Block All-DNS-DomainHost-Blocklist
Selector Operator Value Logic Action Domain in list Domain Blocklist Or Block Host in list Host Blocklist Or Host matches regex .*example\.com