Apple ID
I received this message on my iMac, iPad, and iPhone today. I haven't used my MacBook in several days. I've checked all of my devises and have 2 step authorization activated on all of them. I didn't receive the usual e-mail informing me that someone signed in on a new device, just this on my home screen. Is this something I should be concerned about? Thanks for your help!
MacBook, OS X 10.11