This BBC interview has a #Cloudflare rep David Bellson who describes CF’s observations on internet traffic. CF tracks for example the popularity of Facebook vs. Tiktok. Neither of those services are Cloudflared, so how is CF tracking this? Apparently they are snooping on traffic that traverses their servers to record what people are talking about. Or is there a more legit way Cloudflare could be monitoring this activity?
They are basically MITM (man-in-the-middle) attack all the traffic that passes through their servers. Most Cloudflare defenders will tell you it's not technically MITM as the site operators gives them permission to do that, but the end result is the same.
Even though sites are encrypted, they hold the decryption key, so they can see all traffic in plain text.
One of the reasons no one gives a shit is there is never news about CF making use of that MitM position. But I know they hire data scientists and what corp can resist the urge to monetize data they have access to? So I think it’s just a matter of time before they get caught abusing the vast amount of valuable data they have visibility on.