Disabled WordPress.com sign on due to possible bug

I was starting to get heavy sign ups on the site from bots, and most of the time when I would go delete them, it would cause my server to spike. Figured it was due to having the wordpress.com login available, so I have disabled it for the time being. Not sure if this is something anyone else has experienced but thought I would post anyways, as I am not sure if the users being created are attempts at doing something malicious.

https://www.ads-software.com/plugins/social-connect/