I have recently seen a sizable number of new user registrations on my site running DNN 6.2.5.  I have a custom registration page which normally results in 2 notifications when a new user registers... 1 from the custom form and the other "canned" DNN notification telling me that a new user has registered.

Over the last few days, I'm getting several registrations per day that don't come through the custom registration page, and are suspicious looking email addresses.

I've checked all the security roles that have the ability to add users, and have found no new users in those roles.

Does anyone have any suggestions where I should be looking to find out how this is happening?  Hopefully I've provided enough info.

Thanks in advance