Bundle Crash Fix
by Onako2
Bundle Crash Fix is a server-side mod that blocks a bundle manipulation method used to crash servers, so the server stays up when a player sends it.
What it does
Some players abuse the bundle item to crash a server. The mod stops that crashing method from taking effect, so an attacker who tries it cannot bring the server down. It only needs to be on the server, since the problem lives on the server side and players connecting to it do not need anything installed.
The mod is published for Fabric, Forge, NeoForge and Quilt. Its files cover three game versions, 1.21.2 – 1.21.4, and the latest build for each loader is 1.3.1 for 1.21.4, released on 2025-05-04. It also runs on Paper, Spigot, Bukkit, Purpur, Folia, Velocity, BungeeCord and Waterfall as a server platform. The code is under a custom license and is not open source, though public links for the source code and the issue tracker are available.
Key features
Blocks bundle crashes
Stops the bundle manipulation method that players use to crash a server, keeping the server running.
Protects against malicious players
Malicious players cannot take the server down with this method, which helps server owners keep the world available.
Crafting stays intact
Players can still craft bundles as normal, so the item remains usable while the crash is blocked.
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
Use cases
Public servers
Server owners who open their world to strangers can install the fix to limit how far a single player can knock the server offline.
Who it’s for: Server owners running Fabric, Forge, NeoForge or Quilt on 1.21.2 – 1.21.4, or a Paper, Spigot, Purpur, Folia, Velocity, BungeeCord or Waterfall server, who want protection against bundle-based crashes.
How it compares
Lake Crash Fix is open source under the MIT License and is server-side only, with files for Fabric and Quilt on 1.21 – 1.21.1. Ultima Failsafe System is for NeoForge on 1.21.1 and is optional on either side, released under the MIT License but not open source. Long NBT Killer covers a different crash source, runs server-side only on Fabric, Forge and NeoForge 1.20.1 – 1.21.8, and uses a custom license.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| Bundle Crash Fix | Fabric, Forge, NeoForge and Quilt | 1.21.2 – 1.21.4 | Server-side only | 2025-05-04 |
| Lake Crash Fix | Fabric and Quilt | 1.21 – 1.21.1 | Server-side only | 2024-07-19 |
| Ultima Failsafe System | NeoForge | 1.21.1 | Client or server, optional | 2026-07-09 |
| Long NBT Killer | Fabric, Forge and NeoForge | 1.20.1 – 1.21.8 | Server-side only | 2026-02-03 |
Questions
Does Bundle Crash Fix need to be installed on the client?
Which loader should a server use for Bundle Crash Fix?
Can Bundle Crash Fix run on Paper or Spigot?
In the catalog
Bundle Crash Fix is one of 3,545 Optimization mods on ModsFinder, and one of 2,575 Optimization mods for Fabric. 17,979 mods support Minecraft 1.21.4.
More from Onako2
Similar mods
What the author says
Protect yourself from nasty cheaters trying to crash the server with Bundles! Paper has fixed it in 1.21.4 #226 The plugin versions are licensed under the GNU General Public License v3.0 (GPL-3.0).
Official listing
- Modrinth page
- modrinth.com/mod/bundle-crash-fix
- Owner
- Onako2
- Published
- 2025-05-01
- Updated on Modrinth
- 2025-05-04
- Facts verified
- 2026-10-15