Inspired by wonderful PHP Transparent Reverse Proxy project by https://github.com/michaelfranzl/no.php .
This backdoor file provide access to CPanel API that blocked from public internet (usually by Imunify or another FW) to run certbot-dns-cpanel.
- Create new sub domain site via cpanel. Ensure this subdomain is hard to guess.
- Open file manager, put below file
.htaccess
(prevent file indexing) andno.php
(or you can rename it to hard-to-guess file name) - Testing your backdoor url using simple cURL