Security Vulnerability Update

Last Updated on December 10, 2021 by Kooldude183

Yesterday, I was made aware of a security vulnerability affecting many versions of Minecraft: Java Edition, both clients and servers included. I have recently added a patch to prevent this security issue from affecting all Java players that connect to the server.

However, if you do connect to other servers, you will need to update/modify your client using the steps linked below (this is important if you are using a third party launcher like Badlion or Lunar).

For more information about this vulnerability and how to fix it, please see the Twitter thread from slicedlime (tech lead for Java) here:, or the official Minecraft news post here:–security-vulnerability-java-edition.