April 2018 Mac Cleaner Malware
The instructions from 2015 that reveal how to remove this nonsense is still relevant on that latest Max OS High Sierra (10.13.4). Mine came along with an Adobe Flash update so beware. This just ***** and I'm wondering if Adobe is complicit with this infection. All gone allegedly. We'll see if it randomly crops up again.
MacBook Pro (Retina, 15-inch, Mid 2015), macOS High Sierra (10.13.4)