[JonesMaths]

Need help how this pdf was uploaded on that website. i will reward anyone who can help. thanks

[Bastille]

The website has been made with WordPress (wp-content), WP works a lot with plugins, I've found the "ninja-form" plugin, there is maybe a link with it.

Sometimes plugins are vulnerable and webmasters do not update the plugins to fix the flaw, and they are exploited, for example a vulnerability found in Ninja Form plugin :

https://www.exploit-db.com/exploits/41692