
Samsung Galaxy Ace 4
The latest firmware for Samsung Galaxy Ace 4 (SM-G313M) is G313MUBU0AOI2 with Android 4.4.2 (KitKat), released on September 23, 2015 for 2 regions (CSC). Every official firmware build for SM-G313M, newest first: one row per build with all regions (CSC) that received it.
All 12 builds in our database run Android 4.4.2 (KitKat). The newest build, G313MUBU0AOI2, was released on September 23, 2015. No new build has appeared for 134 months, so regular updates for this model have most likely ended.
Box codes of SM-G313M for different colors and markets. Firmware is chosen by the model code SM-G313M and your region (CSC), not by the SKU.

SM-G935TZK

SM-G930AZK

SM-G935AZS

SM-G935TZS

SM-G935AZK

SM-G935TZD

SM-G975WC

SM-G975FC
The newest firmware for SM-G313M runs Android 4.4.2 (KitKat): build G313MUBU0AOI2, released on September 23, 2015.
The latest build for SM-G313M, G313MUBU0AOI2, was released on September 23, 2015 (11 years ago).
SM-G313M has had no new firmware for 134 months, so regular updates have most likely ended.
Yes, all firmware files for SM-G313M are 100% official, original, and obtained directly from Samsung servers.
To flash SM-G313M, 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-G313M.