I just had a rather interesting experience with one of my websites.
I have it set up, so I get notified when anyone subscribes. Today I got 2 emails back to bac. Normally this would be delightful. Today, these emails did not quite sit right.
As you can see, the domains of email addresses that subscribed are almost identical, and certainly not from any legit domain I am aware of.
So, I went into the site and checked them out. You can find your subscribers in Users. You can sort the complete list by role. I clicked on Subscribers and found both emails.
Because I didn’t feel right about them, I deleted both. If they are legit (which they probably are not) I hope they resub.
While I was there, I noticed another duplicate email with different usernames. For good measure, I deleted those too.
I don’t know if subs can do anything to negatively effect our sites, but better safe than sorry,
Lesson: Pay attention to those subscriber emails.