Files with pubg file extension can be found as files encrypted and affected by a ransomware labeled as PUBG.
PUBG file extension - PUBG ransomware affected data
What is pubg file? How to open pubg files?
File type specification:
The pubg file extension is used by a variant of ransomware called PUBG, which much like other similar threats encrypts users files.
It is distributed via Spam email attachments, drive-by-download, exploit kits, etc.