LunAuth
by O.S. TEAM
LunAuth is a server-side login security mod that requires players to register and authenticate before they can play.
What it does
Standard register and login commands let players set a password and sign in each session. The mod is aimed at servers running in offline mode, where it helps guard accounts against unauthorized access and theft of personal data. Players who have not logged in are held in place with a frozen movement state and a blindness effect, and their interactions stay blocked until authentication succeeds.
Installing the mod on a NeoForge or Fabric server is enough, and the server then generates its configuration file on first launch. Only the server needs it, so players join without installing anything. Files are published for 1.21.1 and 26.2, and the mod is open source under the MIT License, with its source code public.
The author describes the project as a minimalist authentication solution built for modern hardware, with a focus on performance. Older and newer builds do not always work together, so server owners should check the changelog before upgrading.
Key features
Simple authentication
Players register and log in with standard commands, giving each account a password-protected session.
Anti-brute force
Players are kicked automatically after three failed login attempts, which slows password guessing.
Session timeout
The login window is adjustable and defaults to a short period, so unauthenticated players cannot hold a server slot for long.
Player lockdown
Unauthenticated players stay frozen and blinded, and their interactions are blocked until they log in.
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
Use cases
Who it’s for: Server owners running offline mode or private servers who want a simple login step for players. Players need nothing installed on their own clients.
How it compares
Remove Blindness is also server-side only and open source under the MIT License, but it is a NeoForge mod for 1.21.1 and only removes the blindness effect, without a login system. TimeOutFix is a server-side, open-source option under the MIT License for Fabric 1.21.7, aimed at timeout behavior rather than authentication. Both differ from LunAuth in function and loader coverage.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| LunAuth | Fabric and NeoForge | 1.21.1 – 26.2 | Server-side only | 2026-08-25 |
| Remove Blindness | NeoForge | 1.21.1 | Server-side only | 2025-01-17 |
| TimeOutFix | Fabric | 1.21.7 | Server-side only | 2025-08-12 |
Questions
Does LunAuth need to be installed on clients?
Which loaders and versions does LunAuth support?
Can different LunAuth builds be mixed on one server?
In the catalog
LunAuth is one of 36,990 Utility mods on ModsFinder, and one of 25,772 Utility mods for Fabric. 13,894 mods support Minecraft 26.2.
More from O.S. TEAM
Similar mods
What the author says
[ LunAuth ] 🛡️ ⚠️version 1.3.0 is incompatible with 1.2.1⚠️ A minimalist, high-performance authentication solution for Minecraft.
Official listing
- Modrinth page
- modrinth.com/mod/lunauth
- Owner
- O.S. TEAM
- Published
- 2026-05-14
- Updated on Modrinth
- 2026-08-25
- Facts verified
- 2026-10-15