Testei, me retorna isso no console (No localhost:8001):
localhost/:1 Access to fetch at 'http://localhost:8003/destino.php' from origin 'http://localhost:8001' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.
(índice):12
Uncaught (in promise) TypeError: Failed to fetch
at doRequest ((índice):12:9)
at (índice):21:7
doRequest @ (índice):12
(anônimo) @ (índice):21
Promise.then (assíncrono)
doRequest @ (índice):18
(anônimo) @ (índice):21
(índice):18
Warning: file_get_contents(http://localhost:8003/destino.php): Failed to open stream: Cannot assign requested address in /var/www/html/proxy.php on line 28
Warning: Undefined variable $http_response_header in /var/www/html/proxy.php on line 29
Warning: foreach() argument must be of type array|object, null given in /var/www/html/proxy.php on line 31
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