So, belodion, now that the problem persists in safe mode, what is different?
Auto restore of apps, from "settings -> backup&reset -> backup my data" has always been off,
and I have never used any third-party system backup software.
"Third-party" as in .apk files or from google play? It's been a while since my first factory reset, I don't remember what the last apps that I installed were.
How can such an app "survive" a stock rom reflashing?
belodion, No, there where zero installation attempts overnight.
(PS: Can I somehow edit my original post? I made it as a guest)
EDIT: "Airplane" tried to install just now.