This exact thing just happened to me. Galaxy S6, using Android 6.0 (marshmallow), version 6.01, and no, I do not have permission to install from unknown sources turned on. I had not downloaded anything or installed anything recently, but this came up. I ran a scan and it said there are no threats, nor are there any in threat history. "Learn More" just shows "8 common-sense tips to keep your smartphone safe". Can Verizon please let us know what this means?
