Security Testing

Tera

Client:Gameforge (Developer: Bluehole Studio)

Cyrex partnered with Gameforge to conduct iterative black box penetration testing for TERA, securing its custom engine networking, gameplay systems, and in-game economy through real-world attack simulation.

The Challenge

Securing a Custom MMORPG Engine Without Documentation

TERA is a large-scale fantasy MMORPG built on a proprietary in-house engine and custom network protocol. With millions of global players and complex in-game systems, validating security from an external attacker perspective was essential.

Cyrex was engaged under a black box penetration testing model, meaning:

No source code access
No internal documentation
No architectural diagrams

To test the platform effectively, we first performed reconnaissance and reverse engineered the networking structure in order to integrate our tooling.

The scope included:

Network-based packet communication
Player movement and combat physics
Fighting abilities and skill systems
Crafting and resource gathering
Player-to-player trading and the “Grand Exchange”
Duelling systems
Quest logic (start and completion)
Mount mechanics
Guild and party systems
Account registration and authentication
Character creation

For a persistent MMORPG with a live in-game economy, vulnerabilities in progression or trading systems can significantly impact player fairness and platform stability.

The Cyrex Solution

Iterative Black Box Penetration Testing

Cyrex conducted multiple testing iterations, each building upon findings from the previous phase.

Reverse Engineering & Network Analysis

With no documentation available, our team:

Analyzed network packet structures
Reverse engineered client-server communication flows
Extracted functionality from the game client
Developed custom tooling to interact with proprietary protocols

This allowed us to test gameplay systems in a realistic attacker scenario.

Exploit Discovery Across Gameplay Systems

During testing, we identified multiple vulnerabilities across various systems. One high-impact finding allowed players to repeatedly trigger the “quest complete” state, enabling rapid experience farming and reward duplication.

Such flaws directly affect progression balance and in-game economy integrity.

Each iteration revealed additional weaknesses as the testing surface expanded.