How to remediate – Unreal Tournament Server Detection

1. Introduction

Unreal Tournament Server Detection indicates a game server is running on your network. This poses a risk as these servers can be targets for attack, potentially allowing unauthorised access to your systems. Affected systems are typically those used for hosting online gaming, often personal computers or dedicated servers within an organisation’s network. A compromise could lead to data breaches, service disruption and reputational damage.

2. Technical Explanation

The vulnerability arises from the presence of an Unreal Tournament server application running on a host. Attackers can exploit known vulnerabilities in the server software or use it as a pivot point for wider network attacks. Preconditions include the server being accessible over the network and potentially having publicly exposed ports. While no specific CVE is currently associated with simply *running* the server, individual versions of Unreal Tournament have had numerous security flaws identified over time. An attacker could attempt to exploit these flaws remotely to gain control of the server or compromise connected clients.

• Root cause: The presence of an outdated or unpatched Unreal Tournament Server application on a network host.
• Exploit mechanism: Attackers scan for open ports associated with Unreal Tournament servers and attempt to exploit known vulnerabilities in the server software, such as buffer overflows or remote code execution flaws.
• Scope: All versions of Unreal Tournament Server are potentially affected, depending on their age and patch status.

3. Detection and Assessment

Confirming a vulnerable system involves identifying if an Unreal Tournament server is running. A quick check can identify the presence of the service. More thorough methods involve port scanning and version detection.

• Quick checks: Use netstat -an | grep 7777 to see if the default Unreal Tournament port (7777) is open and listening.
• Scanning: Nessus plugin ID 10398 can detect Unreal Tournament servers. This is an example only, results may vary.
• Logs and evidence: Check system logs for processes named “UnrealTournament” or related executables. Event IDs will depend on the operating system.

netstat -an | grep 7777

4. Solution / Remediation Steps

Fixing this issue requires ensuring that running game servers are aligned with security policies. This may involve disabling unnecessary services or implementing stricter network controls.

4.1 Preparation

• Ensure you have access to reinstall the server software if needed. A roll back plan involves restoring from the snapshot or re-enabling the service.
• Change windows may be required for planned downtime. Approval should come from IT management.

4.2 Implementation

1. Step 1: Review your corporate security policies regarding game servers and network access.
2. Step 2: If the server is not required, stop the Unreal Tournament service.
3. Step 3: Disable the Unreal Tournament service to prevent it from automatically starting.
4. Step 4: Consider blocking outbound connections on port 7777 at the firewall if the server must remain installed but unused.

4.3 Config or Code Example

Before

service unreal_tournament status (shows service running)

After

systemctl disable unreal_tournament (disables automatic startup on Linux)

4.4 Security Practices Relevant to This Vulnerability

Several security practices can help prevent this issue. Least privilege limits the impact of a compromise, while network segmentation isolates vulnerable systems.

• Practice 1: Implement least privilege principles by running services with minimal necessary permissions.
• Practice 2: Network segmentation to isolate gaming servers from critical business networks.

4.5 Automation (Optional)

# Example PowerShell script to disable a service
Stop-Service -Name "UnrealTournament" -Force
Set-Service -Name "UnrealTournament" -StartupType Disabled

5. Verification / Validation

Confirming the fix involves verifying that the Unreal Tournament server is no longer running and accessible. A post-fix check should show the service stopped.

• Post-fix check: Run netstat -an | grep 7777; it should return no results.
• Re-test: Re-run the initial detection method (port scan) to confirm that port 7777 is closed.
• Smoke test: Verify other essential network services are still functioning correctly.
• Monitoring: Monitor system logs for any attempts to start the Unreal Tournament service.

netstat -an | grep 7777 (should return no output)

6. Preventive Measures and Monitoring

Preventive measures include updating security baselines and implementing checks in deployment pipelines. Regular patch cycles are also essential.

• Baselines: Update your system baseline to disallow the installation of non-approved gaming software.
• Pipelines: Add a check to your CI/CD pipeline to scan for known vulnerabilities in installed applications.
• Asset and patch process: Implement a regular review cycle for all systems to identify and address outdated or unpatched software.

7. Risks, Side Effects, and Roll Back

Disabling the Unreal Tournament server may impact users who rely on it for gaming. Ensure you have a clear roll back plan in place.

• Risk or side effect 1: Disabling the service could disrupt gameplay for authorised users.
• Risk or side effect 2: Blocking port 7777 may affect other applications using that port (unlikely, but check).
• Roll back: Step 1: Re-enable the Unreal Tournament service using systemctl enable unreal_tournament (Linux) or equivalent Windows command. Step 2: Restart the service using systemctl start unreal_tournament (Linux) or equivalent Windows command.

8. References and Resources

• Vendor advisory or bulletin: N/A – This is a general detection, not a specific vendor flaw.
• NVD or CVE entry: N/A – No specific CVE associated with simply running the server.
• Product or platform documentation relevant to the fix: Unreal Engine Server Administration Wiki