CurseForge · Minecraft mod
CFX
Fabric mod that patches certain hazardous exploits
Quick answer
Which CFX release should I use?
CFX v1.9 targets 1.17.1, 1.16.3, 1.19.3 with Fabric, Quilt. The project page does not say whether this file belongs on the client, dedicated server, or both. No extra mods listed for this file.
Where it goes
Is CFX required on the client, server, or both?
The project page does not say whether this file belongs on the client, dedicated server, or both.
The source does not explicitly classify this release as client-only or server-only.
What else does CFX v1.9 need?
CFX v1.9. Change the file and its required mods may change too.
This file does not list any required mods. Do not add a library just because a different file uses it.
This file does not list any required or optional mods.
Before you install it
Add CFX without breaking your instance.
Built for CFX v1.9. Pick another file and the loader, install side or required mods may change.
- 01
Stick to this file
Use CFX v1.9. It targets 1.17.1, 1.16.3, 1.19.3 with Fabric, Quilt; another release may have different loader, side or dependency requirements.
- 02
Bring the mods it needs
This file does not list any required mods. Do not add a library just because a different file uses it.
- 03
Put it on the correct side
The project page does not say whether this file belongs on the client, dedicated server, or both.
- 04
Pick the file you checked
Use the “Get this file” button beside CFX v1.9. It opens that exact file at the source.
About this project
What does CFX add?
CFX is a Fabric mod for Minecraft 1.14 to 1.21.4 that patches hazardous exploits.
Why?
For almost a decade now, Minecraft exploiting has become increasingly common and increasingly dangerous. While Mojang has been making a commendable effort to combat this by patching exploits in their game with updates, they don't support older, more vulnerable versions of the game. For most people, this isn't a problem, because all they need to do to stay protected is to use the latest and greatest version of Minecraft. However, some people simply can't do that for one reason or another (such as running older hardware or using mods that don't support later versions of the game).
So, this is where CFX steps in. It tries to patch some of the more hazardous exploits for all mainline versions of the game, even the versions that were superseded by minor updates (e.g. 1.14, 1.14.1, 1.15.1, etc). That way, almost everybody can be protected. It works standalone so you don't have to use it as part of a bigger package of mods.
Patch Coverage
This timeline details what patches are available for which exploits.

⚠️: Currently only partially patched in some places. Contributions are welcome to make them complete.
Project description from CurseForge.
Pick your setup
CFX by Minecraft version and loader
Choose the version and loader you play, then open the matching release.
1.21.3
2 loader builds1.21.2
2 loader builds1.21.1
2 loader builds1.21
2 loader builds1.20.6
2 loader builds1.20.5
2 loader builds1.20.4
2 loader builds1.20.3
2 loader builds1.20.2
2 loader builds1.20.1
2 loader builds1.20
2 loader buildsShowing the newest 12 of 36 game versions. Older files are in the list below.
Check the dependencies, then try the file in a copied instance before changing a world you care about.
Recent files
CFX versions and loaders
CFX v1.9
CFX-1.9.jar
8 Jan 2025
CFX v1.8
CFX-1.8.jar
25 Sept 2023
CFX v1.7
CFX-1.7.jar
8 Aug 2023
CFX v1.6
CFX-1.6.jar
7 Aug 2023
CFX v1.5
CFX-1.5.jar
6 Aug 2023
CFX v1.4.1
CFX-1.4.1.jar
4 Aug 2023
CFX v1.4
CFX-1.4.jar
4 Aug 2023
Looking for an older file? The official CurseForge project page is in Resources.