https://www.bleepingcomputer.com/news/security/microsoft-khonsari-ransomware-hits-self-hosted-minecraft-servers/

Microsoft urges admins of self-hosted Minecraft servers to upgrade to the latest release to defend against Khonsari ransomware attacks exploiting the critical Log4Shell security vulnerability.

Mojang Studios, the Swedish video game developer behind Minecraft, released an emergency security update last week to address the bug tracked as CVE-2021-44228 in the Apache Log4j Java logging library(used by the game's Java Edition client and multiplayer servers).