We have developed quite a unique reCAPTCHA check plugin for modified WordPress Network installations.
If you have the need to secure your WordPress Network site admin logins with reCAPTCHA, and you happened to have unique mapped domains to your sites including for wp-admin, you might have noticed that it would be quite a lot of work to generate recaptcha keys for all domains etc. Then you looked at all available plugins, and noticed that non of them have support for recaptchas hostname check, well hello there, then you have arrived at the correct page!
This plugin enables you to add recaptcha to the wordpress admin login of your network sites with a single set of keys, regarding the amount of unique domains, due to verification of hostname on this end.
When generating reCAPTCHA V2 keys, make sure you uncheck ”Verify the origin of reCAPTCHA solutions” under settings, to be able to use the same set of keys on an unlimited amount of domains.
Please note, this plugin is not needed for regular WordPress Network installations, and may require additional modifications to WordPress and you web server, which is not covered by this plugin.
Just head over to Github to get started: https://github.com/jimmysjunfors/wordpress-network-recaptcha