AltAuth
by lixfel
AltAuth lets accounts that are banned or disabled join online-mode servers, by routing session requests through a trusted proxy.
What it does
AltAuth redirects session server requests to a proxy that a server owner has specified, so a banned or disabled account can still join a multiplayer server. Mojang accounts have become unusable for some multiplayer functions, and the mod is built around that case. Whether a join succeeds depends on whether the client and the server both support online-mode connections through the proxy.
Players select which AltAuth proxy servers they trust in the game, and a server running AltAuth can require that a trusted proxy be used. This prevents unauthenticated users from joining. Because a proxy sees the session traffic, the mod warns that trusting an untrusted proxy exposes the account to a malicious proxy server.
AltAuth is published for Fabric and works on either side, and neither side needs it. It is also available for Paper, Spigot, Bukkit, BungeeCord and Waterfall. Files cover 1.19.2 only, with 1.0.0 for 1.19.2 as the latest file, and the mod is released under the MIT License as open source. The author notes that Minecraft accounts up to 48 hours after creation, Mojang accounts and Microsoft accounts all need the proxy in some cases.
Key features
Banned account login
Lets accounts that are banned or disabled join servers that run in online mode.
Proxied session requests
Routes session traffic through a proxy chosen by the server owner, so the server does not contact Mojang directly.
In-game proxy trust list
Players choose which AltAuth proxy servers they trust from within the game.
Unauthenticated join block
A server using AltAuth can allow only trusted proxies, which stops unauthenticated users from joining.
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: Players whose accounts are banned or disabled from multiplayer, and server owners who want to allow those accounts through a chosen proxy.
How it compares
Connecto is server-side only, open source under the MIT License and published for 1.20.2 – 26.2, so players join without installing anything. FriendLink is client and server and open source under the GNU General Public License v3.0 or later, with files for 1.21.1 – 26.1.2. Dissociation is client-side only, not open source, under the MIT License and covers 1.21 – 26.2, so it changes only the client.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| AltAuth | Fabric | 1.19.2 | Client or server, optional | 2022-10-06 |
| Connecto | Fabric | 1.20.2 – 26.2 | Server-side only | 2026-08-12 |
| FriendLink | Fabric | 1.21.1 – 26.1.2 | Client and server | 2026-05-20 |
| Dissociation | Fabric | 1.21 – 26.2 | Client-side only | 2026-06-21 |
Questions
Does AltAuth need to be installed on both sides?
Which Minecraft versions does AltAuth support?
Is it safe to trust an AltAuth proxy server?
In the catalog
AltAuth is one of 5,392 Social mods on ModsFinder, and one of 4,084 Social mods for Fabric. 12,559 mods support Minecraft 1.19.2.
Similar mods
What the author says
AltAuth has not been updated to recent Minecraft versions. Since Mojang accounts have become completly unusable I have no need anymore for the modification, although the banned and multiplayer disabled accounts functionality should still work. AltAuth is a solution to allow players with Mojang account, (untested)…
Official listing
- Modrinth page
- modrinth.com/mod/altauth
- Owner
- lixfel
- Published
- 2022-10-06
- Updated on Modrinth
- 2022-10-06
- Facts verified
- 2026-10-15