Is sftp secure when using cloudflare?
I build an Application which captures screenshots and sends it to a WordPress website through sftp. I wonder how cloudflare can be used securely like this as it can be bypassed by this open port. Is using sftp on a cloudflare hosted website secure?
You need to use a Code Signing Certificate
Make sure that you use a Code Signing Cerificate to encrypt your software and to make sure that the software will not be altered by anybody.
And if you want to protect the new application with cloudflare then you should build a web application whichs allows a login via the website itselve. Like this you can make sure that the user will login through the same side wide IP which is protected over cloudflare.