Users often "dump" their own legitimate games to pkg format using homebrew tools.
A PKG is essentially the file format Sony uses to package and distribute all types of software for its PlayStation consoles, including full games, updates, downloadable content (DLC), and even system software. The structure is heavily secured, with a signed header and an encrypted image that uses strong encryption to protect its contents. Ps5 Pkg Games Download
For standard users, interacting with PKG files happens securely through official remote download features. Remote Downloading via Web Browser Users often "dump" their own legitimate games to