CVE-2021-43819
📋 TL;DR
This vulnerability in Stargate-Bukkit Minecraft mod allows minecarts with chests to duplicate items when teleporting through portals, breaking game economy and integrity. It affects all Minecraft servers running vulnerable versions of the Stargate-Bukkit mod. The issue impacts server administrators and players on affected servers.
💻 Affected Systems
- Stargate-Bukkit Minecraft mod
📦 What is this software?
Stargate Bukkit by Stargate Bukkit Project
⚠️ Risk & Real-World Impact
Worst Case
Malicious players could exploit this to duplicate valuable items, causing severe economic imbalance, server inflation, and potentially crashing the server through resource exhaustion.
Likely Case
Players accidentally or intentionally duplicate items, disrupting server economy and requiring administrative intervention to restore balance.
If Mitigated
With proper monitoring and administrative oversight, duplicated items can be detected and removed, but server integrity remains compromised until patched.
🎯 Exploit Status
Exploitation requires player access to create/use minecarts with chests and portals. No authentication bypass needed beyond normal gameplay access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 0.11.5.1
Vendor Advisory: https://github.com/stargate-bukkit/Stargate-Bukkit/security/advisories/GHSA-64r2-hfr9-849j
Restart Required: Yes
Instructions:
1. Stop Minecraft server. 2. Backup server files. 3. Download Stargate-Bukkit version 0.11.5.1 or later. 4. Replace old Stargate-Bukkit JAR file in plugins folder. 5. Restart server.
🔧 Temporary Workarounds
Disable minecart teleportation
allTemporarily disable teleportation of minecarts through Stargate portals
Edit server configuration to disable minecart teleportation in Stargate settings
🧯 If You Can't Patch
- Disable Stargate portals entirely until patching is possible
- Implement strict monitoring and manual item removal for suspected duplication
🔍 How to Verify
Check if Vulnerable:
Check Stargate-Bukkit plugin version in server logs or plugins folder. If version is below 0.11.5.1, server is vulnerable.Check Version:
Check server startup logs for 'Stargate-Bukkit vX.X.X' or examine the JAR filename in plugins folderVerify Fix Applied:
After updating, test minecart with chest teleportation - items should not duplicate. Check server logs for successful plugin load of version 0.11.5.1+.📡 Detection & Monitoring
Log Indicators:
- Unusual item quantity changes
- Rapid minecart teleportation events
- Player reports of duplicated items
Network Indicators:
- Increased server resource usage during teleportation events
SIEM Query:
Search for patterns of minecart teleportation followed by inventory changes without corresponding item removal