Adware keeps installing itself I have somehow got my phone infected with an adware by the name 'Android Communication Sync' ('com.foreign.provider').

It isn't visible in the apps browser (doesn't have any icon) and causes ads to occassionally display out of nowhere.

I have tried to uninstall it multiple times, but everytime I find it installed on my phone after a few days (it appears in Settings -> Apps -> Downloaded). 

My current solution is to disable (freeze) it, so that it atleast doesn't disturb with me ads.

How can I remove it and prevent it from getting installed again?

My phone is a rooted Micromax Unite 2 (Micromax A106) running Android 4.4.2. As far as I remember, I haven't installed any app outside of Google Play Store except Adaway.

Here is its apk I exported using Link2SD.
It is possible for adware, as well as other "viruses" to be installed on the sd card. Thus even doing a factory reset can reinstall the "virus". If you have access to a pc with virus protection on it. You can mount the phone as a USB storage and scan it from there. Besides wiping both the phone and the sd card. There may not be a permanent fix. But if you are able to locate the file and delete it from there. That may fix it.