Does Cloudflare tie "known bots" to IP address, and what if they change?

I’ve been using the “known bots” rule to make sure that we don’t inadvertently block known, friendly bots (in particular, Google).

I wondered, does Cloudflare tie known bots to their respective known IP address ranges? I’m guessing they must, otherwise an attacker could simply spoof their user-agent as “GoogleBot” or “Yandex”, etc and get around firewall rules easily.

But in addition to that, what if a Bot’s IP address range changes (or they introduce new IP ranges)? I just wondered how it was possible for the folks at Cloudflare to stay on top of this in a reliable way?

I guess what I’m worried about is waking up one morning to find our websites all vanished from Google because it’s been inadvertently blocked.

In general yes.

All well behaved Bots publish a mechanism to validate their IP addresses. In the case of Google it is published here:, Bing and Yandex use the same technique.

I don’t know how CF manage this internally, but I would expect this is not done in real-time, and that they also have a relationship with the main bots to flag any changes.

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