Java security issue affects Minecraft servers

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On December 9th, 2021, a log4j Java security issue was discovered which can affect a number of programmes and apps, including Minecraft.

Staff at Minecraft’s Mojang studios, and those working at third-party servers such as PaperMC and Forge, have been working tirelessly to implement patches to fix the problem. As such, players have been advised to close all instances of Minecraft and update to the latest patch if possible. However, this issue only affects online multiplayer or modded Minecraft, and anyone who only plays single-player Vanilla Minecraft shouldn’t worry. Keep reading to find out everything we know about this security issue.

lava minecraft security breach

What is the Java security issue?

While not much information has been released about the knock-on effects of the breach, we do know that it is affecting multiplayer servers and Minecraft modpacks. In other words, it seems hackers may be able to gain access to other systems through the chat system in these multiplayer worlds.

Am I affected?

Again, the majority of casual Minecraft players won’t be affected by this. If you just play on Vanilla (i.e. not modded) single-player worlds, then you will not be affected by this issue. However, you should probably still restart the launcher to get access to the latest version of Minecraft.

On the other hand, if you run a multiplayer server, are part of a multiplayer server, or play any modded Minecraft worlds, single- or multiplayer, you should close down any instances of Minecraft that you currently have open and await further instruction relative to your Minecraft experience. For example, if you play a server on an older version of Minecraft, keep an eye on Mojang updates for that version, and information from your server provider.

This issue does not affect console players at all.

What should I do if I might be affected?