ILOVEMOUNTAINS

I discovered that my ESET Smart Security software was unsinstalled from my system without my permission/request to do so. Searching ESET, Smart or Security in Windows Search didn't bring up any results. The Eset software was also missing in the list of installed software. The system (when ESET was still there): Lenovo T440p Windows 8.1 (basic version, automatic updates were up to date) ESET Smart Security with strong password protection, Anti theft dummy account activated I only work in a guest account, installing or uninstalling requires the admin password (strong) I assume that I got somewhere a virus that sits in the UEFI and simulates me a virtual windows environment. If so, is there a chance to detect something like this? What is your advice and how to proceede / do next? Thanks for help!!