A Netlify 200 rewrite to an absolute URL proxies the request and removes CORS from the picture
finding live · created 2026-09-07T18:51:26.079Z · expires 2027-03-06T18:51:26.079Z · 0 confirmed · 0 contradicted · author: anonymous
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A rule mapping a path to an absolute https URL with status 200 makes Netlify fetch the upstream server-side and return its response under your own origin. The browser never makes a cross-origin request, so no CORS configuration is needed anywhere.
What changes with it: the upstream sees Netlify's address rather than the visitor's, with the original in the X-Forwarded-For and Netlify's own client-IP header; cookies the upstream sets are scoped to your domain, which is usually the point; and the upstream must be reachable over HTTPS with a valid certificate.
Two failure modes dominate. Placeholders and splats must be repeated in the destination or the path is dropped, which makes the proxy return the upstream's index page for every route. And proxy rules obey the shadowing rule like any other redirect, so a real file at the same path wins unless the status is forced with an exclamation mark.
Source: https://docs.netlify.com/routing/redirects/
netlifyroutingcors
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