Plugin: ruigehond-embed (Used by 10 domains)

Plugin to embed selected urls from your site elsewhere.

Security

Other embedding will be prohibited by default, with an X-Frame-Options header and, optionally, a Content Security Policy header.
This will secure your WordPress website from a number of fairly easy attacks.

To make this plugin especially useful you can now allow (third party) websites to embed specific urls from your site.
Easily reuse forms or other content from your main site on satellite sites you own, without opening up any of them to attack.

Quick setup

Activate the plugin and go to Settings -> Ruigehond embed.
Add a reference (e.g. general-contact-form) in the title field and save the settings.
Add a slug it should serve (e.g. /contact-clean/) in the embed field.
Add urls that may embed this, aka referrers, (e.g. https://my-satellite.site) in the textarea.

Embedding

Install the plugin on your satellite site. This has the added benefit of locking down that site as well.

Use the simple shortcode on that site to generate an iframe with the embedded content:
[ruigehond-embed src="https://my-main.site/ruigehond_embed/general-contact-form"]

Watch the form magically and safely be embedded. Other sites will continue to not be able to embed your content.

You can also embed using a regular iframe in html, as long as the referrer is whitelisted.
However, by using the plugin and shortcode, the height of the iframe will automatically be adjusted to fit the content.

Use htaccess

This plugin adds lines (clearly marked) at the beginning of your htaccess file.
They need not be at the beginning, but they need to be before the WordPress lines, or any other lines that corrupt the THE_REQUEST var.

This plugin needs mod_headers, mod_rewrite and mod_setenvif to be activated, but they probably already are.

Without htaccess

When the htaccess is not processed, the plugin itself works directly with the request in the php processor.
The CSP header is not supported in that case.
Also, other plugins (especially caching plugins) may already have decided on a different route and this plugin might not work.

Content Security Policy

You can switch on the Content Security Policy (or CSP) header in this plugin, which is the most modern way to tackle these issues.
However, other plugins may interfere, so be sure to check whether the CSP header is to your liking in practice.

This plugin will add a CSP header if none is present yet.
But if one is present, the frame-ancestors directive must be present in it for this plugin to work.
It will only set the frame-ancestors directive, none of the others (to not break your site).