The removal of the _cfuid cookie

Some of us have been relying on this for things like rough rate-limiting or log-batching, will there be any replacement header we can use?


you could create your _uid cookie.


Of course, just checking if it’s going to be replaced with something that’s not cookie based.

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Sorry, I don’t know much about this. The _cfuid cookie is a general Cloudflare feature not specific to Workers.

CF probably realized the value of a GDPR-free, Cookie-free base product, that many jurisdictions are legislating against, and referring to Cookies by name, can just be equally replaced with TLS session tickets/session IDs being the exact same thing (separating clients behind CGNAT/NAT).

As use of cleartext HTTP basically is reaching zero because of multiple policies/dogma/audits/consultants.The chances of a cleartext HTTP site having dynamic content to DDOS off the internet is zero. Attempting to DDOS a static site, well, is the CF continuous testing suite? :grin:

So yeah, CF probably uses TLS tickets/IDs as a replacement for __cfduid but those are invisible at layer 7. You could try to analyze the bits in Cf-Ray header and if any of the bits are stable req to req to req on same phone, then on another phone but same ISP/big 3 provider, the same 3 reqs had stable but different bits. The mask of the stable fields of would be a rough estimate of what is the UUID in a cf-ray header.

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I’m aware, just wanted to know if it was replaced with something else, guessing what parts of the UUID would be usable is not as reliable as proper client tracking.