In December 2021, Log4Shell (CVE-2021-44228) hit the internet. Minecraft servers were some of the first targets. A player could type a chat message and get remote code execution on the server. Millions of servers were vulnerable.
That was three years ago. New vulnerabilities keep appearing. If you run a Minecraft server in 2026, here is what you need to know about security.
What Is a CVE?
CVE stands for Common Vulnerabilities and Exposures. It is a public database of known security flaws. Each vulnerability gets a unique ID like CVE-2021-44228.
When a CVE affects software your server uses (Java, Paper, Pterodactyl, Linux kernel), you need to patch it. The time between public disclosure and active exploitation is often measured in hours, not weeks.
Categories of Risk
1. Java Runtime Vulnerabilities
Your Minecraft server runs on Java. Java releases security patches quarterly. Running an outdated Java version means running with known security holes.
Action: Update Java regularly. Use Java 21 LTS (the current long-term support version). Avoid Java 8 and 11 unless your server software specifically requires them.
Check your Java version:
java -version
2. Server Software Vulnerabilities
Paper, Spigot, and Vanilla Minecraft itself occasionally have security issues. Paper is the fastest to patch because it has an active development team.
Action: Keep Paper updated. Run the latest build for your Minecraft version. Paper publishes security patches within hours of discovery.
3. Plugin Vulnerabilities
Plugins are third-party code running with full server access. A poorly written plugin can expose your server to SQL injection, remote code execution, or data leaks.
Action:
- Only download plugins from trusted sources (SpigotMC, Modrinth, Hangar)
- Check the plugin's last update date. Abandoned plugins are risky
- Remove plugins you no longer use
- Review plugin permissions (does an economy plugin really need file system access?)
4. Panel Vulnerabilities
If you run Pterodactyl or another panel, it is also attack surface. Pterodactyl has had CVEs in both the panel and Wings (the daemon).
Action: Keep Pterodactyl updated. Subscribe to their security announcements on GitHub.
5. Operating System Vulnerabilities
The Linux server underneath everything needs updates too. Kernel vulnerabilities, OpenSSL bugs, and system library issues all affect your server.
Action: Run sudo apt update && sudo apt upgrade regularly. Enable automatic security updates:
sudo apt install unattended-upgrades
sudo dpkg-reconfigure unattended-upgrades
Practical Security Checklist
Network Security
| Action | Why | |---|---| | Only open ports you need (25565/tcp, 19132/udp for Geyser) | Every open port is an attack surface | | Use a firewall (ufw on Ubuntu) | Block unexpected connections | | Enable DDoS protection | Game servers are DDoS targets | | Do not expose your panel on default ports without SSL | Prevents credential theft |
Server Security
| Action | Why | |---|---| | Set online-mode=true | Prevents unauthorized account access | | Use a whitelist for private servers | Blocks random joins | | Install an anti-cheat (Grim, Vulcan) | Prevents exploits that crash the server | | Disable command blocks if not needed | Command blocks can be exploited | | Limit operator accounts | Fewer OPs means less risk from compromised accounts |
Backup Security
| Action | Why | |---|---| | Automate daily backups | Recover from any disaster | | Store backups off-server | Ransomware encrypts local backups too | | Test backup restoration quarterly | A backup that does not restore is worthless |
DDoS Attacks
DDoS (Distributed Denial of Service) attacks flood your server with traffic until it goes offline. Game servers are frequent targets, especially if a banned player wants revenge.
Protection options:
- Host with DDoS protection included: Space-Node includes DDoS protection on all plans
- Use a proxy like TCPShield or Cosmic Guard: These hide your server's real IP and filter attack traffic
- Never share your server's real IP: Use a domain name that points through a proxy
What to Do After a Security Incident
If you suspect your server was compromised:
- Stop the server immediately
- Change all passwords: Panel, database, SFTP, SSH
- Check for unauthorized files: Look for unknown .jar files in plugins/, scripts in the root directory
- Review console logs: Look for unknown commands executed, unusual player activity
- Restore from a clean backup: The safest recovery is restoring from a backup you know is clean
- Update everything: Java, Paper, plugins, OS packages
Staying Informed
- Subscribe to the Paper Discord for security announcements
- Watch the Pterodactyl GitHub for CVE notices
- Follow java.com/security for Java updates
- Check cve.mitre.org for new disclosures affecting your software stack
Security is not a one-time setup. It is ongoing maintenance, just like any other part of running a server.
Space-Node servers include DDoS protection, automatic backups, and run on maintained infrastructure. Focus on building your community while we handle the infrastructure security. Check the plans here.
