S938NKSSDDZJ2 – Galaxy S25 Ultra firmware

Build S938NKSSDDZJ2 is a security update for the Galaxy S25 Ultra (SM-S938N) on Android 17 (One UI 9). It first appeared on Samsung's servers on Oct 18, 2026 (method) and has reached 4 regions so far. It raises the bootloader bit from 12 to 13: once installed, the device no longer accepts firmware with bit 12 or lower, so a downgrade to S938NKSUCDZIF is blocked. Samsung still serves this file.

Model
SM-S938N
Android
Android 17
Type
Security
Bootloader bit
13
First released
Oct 18, 2026
Regions
4

Rollout timeline by region

The date each region code (CSC) first received S938NKSSDDZJ2, counted from the first release.

CSCRegionReleasedRolloutVersion (PDA/CSC/MODEM)
KOOSouth KoreaOct 18, 2026day 0S938NKSSDDZJ2/S938NOKRDDZJ2/S938NKSSDDZJ1
KTCSouth Korea (KT)Oct 18, 2026day 0S938NKSSDDZJ2/S938NOKRDDZJ2/S938NKSSDDZJ1
LUCSouth Korea (LG U+)Oct 18, 2026day 0S938NKSSDDZJ2/S938NOKRDDZJ2/S938NKSSDDZJ1
SKCSouth Korea (SKT)Oct 18, 2026day 0S938NKSSDDZJ2/S938NOKRDDZJ2/S938NKSSDDZJ1

Download and release notes

samloader download -m SM-S938N -r KOO -v S938NKSSDDZJ2/S938NOKRDDZJ2/S938NKSSDDZJ1

Samsung's release notes and security patch level for this update: SM-S938N / KOO on doc.samsungmobile.com. What each part of the build number means: decode S938NKSSDDZJ2.