The same update could be legally obtained via official Nintendo eShop on a non-modded 3DS, but not as a standalone CIA. The CIA version is created by repackaging the eShop download or dumping from an updated console.
Update 1.2 for Pokémon Ultra Sun (and Ultra Moon) is a critical performance and stability patch primarily released to resolve game-breaking bugs that affected both competitive play and general gameplay. Key Patch Highlights Move Glitch Fixes: Pokemon Ultra Sun- Update 1.2 3DS -WORLD- CIA -...