This is my first question on this forum so please let me know if I need to clarify anything.
My Android 10 Pixel 2 just downloaded 2 files without my permission today, both named something to the effect of "Coronovirus+Vaccine+Phase1+Consent+Form.pdf". Obviously suspicious, especially in these times.
I deleted the PDFs without opening them and then scanned for malware on my phone with both Avast and Norton. No malware was found.
I also removed storage permissions for almost everything except for a small handful of apps that need to access storage to function properly.
Prior to this, I've been using 2fa on the google account that is attached to the phone - I even just switched to a physical key as an additional precaution.
My antivirus software found malware on one of my phone apps about 2 days ago, and I deleted that app then (a rescan showed no malware), but that doesn't explain how the suspicious behavior that happened today is possible.
A note on this app - there don't seem to be any Play Store reviews that complain about malware except for 1 that said that it was downloading updates to itself without permission.
How could these PDFs have been downloaded without my permission, and what further measures can I take to protect myself?