Receiver firmware isusually a one way system, if sent from satellite.
Manufacturers sites with free to air products (not the importer/distributor/company brand) may have downloads which can be stored for future use on a PC - If you have the background of the unit - rear panel / specification similarities to a product on a Korean site, this may be the one you need. But be careful.
There are exceptions, for example if channel edit facilities exist, or if the rear panel port (RS232 usually) is disabled by firmware to prevent information on the source from being discovered.
I did have a large amount of info on receiver clones and alternative source upgrades on thre company PC in 2002. The increase in the number of brand names, importer routes and product spec changes has made this rather obselete now.