: PKG installation is only possible on consoles running specific, exploitable firmware versions (e.g., 5.05, 6.72, 9.00, or 11.00). Kernel Exploits & WebKit
If a newly released PKG game requires a higher system firmware version (e.g., firmware 10.00) than the jailbreak firmware active on your console (e.g., firmware 9.00), the game will refuse to launch. The community solves this using a process called . Special tools decrypt the game's executable files and rewrite them to be compatible with lower firmware standards, packaging them into a secondary "backport PKG" that must be installed directly after the base game. Essential Safety and Legal Disclaimers
: These are "dumped" versions of games with modified verification. They are used primarily on jailbroken consoles to run games and homebrew without a traditional license. How to Download PS4 PKG Games Legally