Chrome then Google Play opens randomly`

[AC Question]

Running Android 5.1 on a Hudl 2 tablet. At seemingly random intervals Chome suddenly displays followed immediately by Google Play inviting me to download the CM Security antivirus app. It is not an app I have ever wanted. Tried factory reset and selectively reinstalling my apps but it still happens. Cant find any virus. What do I try next?

 

[B. Diddy]

Welcome to Android Central! You probably installed some adware inadvertently along with some other app at some point. Uninstall apps one by one until it goes away. If you have anything else from Cheetah Mobile, uninstall it immediately. They're notorious for this kind of rubbish.