Is it possible to disable POST from another server somehow?

Question

Apache HTTP Server

There is an old project. Someone uses CSRF to send mail to mailboxes of partner companies.
Could you advise how to protect against sending messages through the form at a lower cost? The captcha is worth it.

I suspect that some kind of script is posting the necessary fields to the right address. Decided that it is possible to forbid POST from all hosts/IP except the. Is it possible to do so?

Answer 1

A POST request is sent not by the server, but by the client, and filtering all this stuff by IP will not work.
google for CSRF-token for your PL