What is ExploitPreventer?

ExploitPreventer is a free, open-source Fabric mod for Minecraft that protects your client from known server-side exploits, including sign translation vulnerabilities, local HTTP request attacks, and device fingerprinting via resource packs.

What Minecraft versions does ExploitPreventer support?

ExploitPreventer currently supports Minecraft 1.21.1 with Fabric Loader. Support for additional versions is planned.

How do I install ExploitPreventer?

Install Fabric Loader and Fabric API for Minecraft 1.21.1, download the ExploitPreventer .jar file, and place it in your Minecraft mods folder. The mod works automatically with zero configuration.

What exploits does ExploitPreventer block?

ExploitPreventer blocks three types of exploits: sign translation key attacks that reveal your installed mods and language, local HTTP requests via resource packs that probe your machine, and device fingerprinting through resource pack cache correlation.

Is ExploitPreventer safe to use on servers?

ExploitPreventer applies non-invasive, client-side protections and does not modify gameplay. However, it is provided as-is under the MIT License and the maintainers accept no responsibility for potential consequences.

ExploitPreventer

Protect your Minecraft client from known server-side exploits

✓ Supported Version: 1.21.1 | More versions coming soon

↓ Download ★ GitHub

Protections

What It Protects You From

Sensible, non-invasive protections enabled by default

🛡

Sign Translation Protection

Prevents servers from exploiting translation key resolution on sign and anvil edit screens. Stops them from detecting your installed mods and language settings.

🌐

Local Request Blocking

Blocks resource pack URLs pointing to local IP addresses like 127.0.0.1 or localhost. Prevents servers from probing for services running on your machine.

🔒

Anti-Fingerprinting

Uses per-account resource pack cache directories to prevent cross-session client tracking. Stops servers from correlating your sessions through resource pack data.

Simple

How It Works

Zero configuration required — just install and play

Install

Drop the mod into your Fabric mods folder

Play

Join any server as you normally would

Protected

Exploits are automatically blocked in the background

⚠ Important

Use At Your Own Risk

ExploitPreventer is provided as-is under the MIT License. While it aims to protect against known exploit vectors, no security tool is perfect. The maintainers accept no responsibility for potential account bans or other consequences.

Note: Plugin channel communications are intentionally not restricted by this mod, as blocking them could break legitimate mod functionality.

📄 View on GitHub

🚨 Exposed

Hall of Shame

Servers and plugins caught using these exploits against players

⚙ Servers

Server	Translation Key	Fingerprinting	Local HTTP	Working
cytooxien.net	✔	✔	✔	✔
mc.blockgame.info	✔	—	—	✔
minevn.net	✔	—	—	✔
mcpvp.club	✔	—	—	✔
donutsmp.net	✔	—	—	✔
play.ccnetmc.com	✔	—	—	✔
netherite.gg	✔	—	—	✔
play.firemc.fun	✔	—	—	✔
applemc.fun	✔	—	—	✔
hugosmp.net	✔	—	—	✔
pixel-mc.net	✔	—	—	✔
boholsmp.ultramc.co	✔	—	—	✔

🔌 Plugins

Plugin	Exploit Used	Source	Working
EXMNT	Translation Key	GitHub ↗	✔
TotemGuard	Translation Key	GitHub ↗	✔

Get It Now

Download

Grab the latest version and protect yourself in under a minute.

↓

Download ExploitPreventer v0.1.10 for Minecraft 1.21.1

Currently supports Minecraft 1.21.1 only. More versions coming soon.

Required:

📦 Fabric Loader ↗ 🔌 Fabric API ↗

Installation

Install Fabric Loader Download from fabricmc.net, select version 1.21.1
Get Fabric API Download from Modrinth and place in your mods folder
Download ExploitPreventer Use the download button on the left
Drop into mods folder %appdata%\.minecraft\mods ~/Library/Application Support/minecraft/mods ~/.minecraft/mods

🎲 Launchers

CurseForge — Create a Fabric 1.21.1 profile, click "Add More Content" or drop the .jar into the profile's mods folder
Lunar Client — Enable Fabric Loader in Lunar, then place the mod in .lunarclient/offline/multiver/mods
Prism Launcher — Create a Fabric 1.21.1 instance, right-click → "Edit" → "Mods" → drag the .jar in
Modrinth App — Create a Fabric 1.21.1 profile, click "+" or drop into the profile's mods folder
Feather Client — Select Fabric 1.21.1, place the .jar in the Feather mods directory