Using HTTP/3 w/ Warp on Cloudflare Websites Shows Private IP

I’ve noticed when using Warp, specifically Cloudflare for Teams, when I visit a Cloudflare site in my browser that has HTTP/3 enabled, my IP on the /cdn-cgi/trace page is now a private IP, which can block some websites from my use. For example, Badlion,, throws an error 1020 at me for using a private IP. I’ve attached some screenshots showing the errors and the /cdn-cgi/trace page.



Well…that’s certainly a problem. Maybe @LucasCF and/or @kkrum know if this is a known byproduct.

Potentially the same problem that this thread saw?

1 Like

I can reproduce this with any Cloudflare-served website by returning a forged A record pointing to in response to DNS queries, regardless it being HTTP/3 or not. I can’t get Chrome to upgrade to HTTP/3 with Warp here. Command: google-chrome --user-data-dir=/tmp/$RANDOM --enable-quic --quic-version=h3-29.

Just wanted to add, HTTP/3 seems to only work on hostnames, not IP addresses, so won’t load as HTTP/3, but will. The screenshot with the blurred IP is without WARP, one with the private IP is with WARP. Also, I realize it says “warp=off,” but I assure you it is on for the second screenshot. This also seems to be a bug when using HTTP/3 with WARP. My laptop is definitely not connected to some secret internal Cloudflare WiFi.

This topic was automatically closed 5 days after the last reply. New replies are no longer allowed.