
Samsung Galaxy C8
Every official firmware build for SM-C710X, newest first: one row per build with all regions (CSC) that received it.

SM-C710F

SM-C701X

SM-C900X

SM-C500X

SM-C5018
You can find the firmware on the model: SM-C710X page.
Yes, all firmware files for SM-C710X are 100% official, original, and obtained directly from Samsung servers.
To flash SM-C710X, you need to download the appropriate firmware, put your device into Download Mode, and use the Odin tool to load the BL, AP, CP, and CSC files.
Downgrading is only possible if the bootloader version (binary bit) of the old firmware matches the current one. Always check the binary version before flashing SM-C710X.