F966NKSSECZK1 – Galaxy Z Fold7 firmware
Build F966NKSSECZK1 is a security update for the Galaxy Z Fold7 (SM-F966N)
on Android 17 (One UI 9). It first appeared on Samsung's servers on Nov 11, 2026 (method) and has reached
4 regions so far. It raises the bootloader bit from 13 to 14: once installed, the device no longer accepts firmware with bit 13 or lower, so a downgrade to F966NKSUDCZJ8 is blocked. Samsung still serves this file.
- Model
- SM-F966N
- Android
- Android 17
- Type
- Security
- Bootloader bit
- 14
- First released
- Nov 11, 2026
- Regions
- 4
Rollout timeline by region
The date each region code (CSC) first received F966NKSSECZK1, counted from the first release.
| CSC | Region | Released | Rollout | Version (PDA/CSC/MODEM) |
|---|---|---|---|---|
KOO | South Korea | Nov 11, 2026 | day 0 | F966NKSSECZK1/F966NOKRECZK1/F966NKSSECZK1 |
KTC | South Korea (KT) | Nov 11, 2026 | day 0 | F966NKSSECZK1/F966NOKRECZK1/F966NKSSECZK1 |
LUC | South Korea (LG U+) | Nov 11, 2026 | day 0 | F966NKSSECZK1/F966NOKRECZK1/F966NKSSECZK1 |
SKC | South Korea (SKT) | Nov 11, 2026 | day 0 | F966NKSSECZK1/F966NOKRECZK1/F966NKSSECZK1 |
Download and release notes
samloader download -m SM-F966N -r KOO -v F966NKSSECZK1/F966NOKRECZK1/F966NKSSECZK1Samsung's release notes and security patch level for this update: SM-F966N / KOO on doc.samsungmobile.com. What each part of the build number means: decode F966NKSSECZK1.