[TProUserOnSprint]

So after using a generic microusb charger all last night, I woke up this morning to some sort of unlock screen. It had red green and blue stripes and a title at the top that said "Security Unlocked". Below that was some other random gobbledegook. I did a soft reset and it booted up normally but its a little disconcerning. It goes without saying I won't use that charger again, but I'm curious as to what might have happened. Any thoughts?

BTW it's on a Stock Sprint ROM