I have disabled registration, yet a .ru person did register

On CB settings I have set "Allow user registration" to "Same as CMS, and
And on the Joomla settings I have set "User option"->"Allow user registration" to "NO".
I trust that that should suffice.

Yet a .ru user did manage to register. How did that happen?
Can you still register if you know how??
(meaning that the "Not allowing user registration" just means that the user registration link is never shown,
but the link is still working if you know how to invoke it, or ??)

Since admin approval is still required there is no harm done, it is just annoying.

That will disable Joomla and CB registration, yes, but if you've any other extensions with their own registration flows then it's possible they registered that way. Try to navigate to the below pages. They should all be inaccessible giving a not authorized error.

Joomla:
index.php?option=com_users&view=registration
index.php?option=com_users&view=registration.register
CB:
index.php?option=com_comprofiler&view=registers
index.php?option=com_comprofiler&view=saveregisters

Thank you.
The first three behaved as expected (and wanted).
The fourth example told me that my session cookie had expired.
So maybe if I can fix myself a valid session cookie...??

The fourth example told me that my session cookie had expired.
So maybe if I can fix myself a valid session cookie...??

That's working as expected. It's a form POST endpoint so if the CSRF token is missing it will output that. Looks like your registration is safely off. Do you have any other extensions installed that might have registrations?