Knowledge Base

Understanding Security in Virtual Worlds.

Understanding Fast-Tracking Attacks in Second Life

In Second Life, "Fast-Tracking" attacks refer to techniques where an attacker moves through a protected area at high speeds to bypass security systems, exploiting the limitations of LSL's detection mechanisms like llSensor or llSensorRepeat. These attacks leverage the fact that LSL sensors have a minimum scan interval (typically 1 second or more) and can miss fast-moving avatars or objects. Below, we’ll explain how to protect and detect against Fast-Tracking attacks, estimate the expected speeds needed to bypass common security systems, and provide LSL-based strategies to mitigate these vulnerabilities.

1. Understanding Fast-Tracking Attacks

  • Mechanism: An attacker uses a high-speed vehicle, flight assist, or external tools (e.g., modified viewers) to move through a protected area faster than the security system’s detection cycle. For example, if a sensor scans every 2 seconds, an avatar moving faster than the sensor’s range divided by the scan interval can pass through undetected.
  • Common Tools: Attackers may use scripted vehicles, teleportation hacks, or physics exploits to achieve high speeds (e.g., 50–200 m/s or more).
  • Impact: The security system fails to detect or respond to the intruder, allowing unauthorized access or griefing.

2. Expected Speeds to Bypass Common Security Systems

The speed required to bypass a security system depends on the sensor range and scan interval. Here’s how to calculate it:

Sensor Range and Scan Interval:

  • Most LSL security systems use llSensorRepeat with a range of 10–96 meters (96m is the maximum for llSensor).
  • The minimum scan interval for llSensorRepeat is typically 1 second, though many systems use 2–5 seconds to reduce lag.

Bypass Speed Calculation:

Formula: Speed = Sensor Range / Scan Interval

Examples:

  • 10m range, 2s interval: Speed = 10 / 2 = 5 m/s (18 km/h, easily achievable with a fast walk or basic vehicle).
  • 50m range, 2s interval: Speed = 50 / 2 = 25 m/s (90 km/h, requires a scripted vehicle or flight assist).
  • 96m range, 1s interval: Speed = 96 / 1 = 96 m/s (345 km/h, requires advanced vehicles or exploits).

In practice, attackers often aim for 50–200 m/s to bypass most systems, as many use longer intervals (2–5s) or smaller ranges (20–50m).

Real-World Context:

  • A typical avatar walking speed is 5–7 m/s; running is ~10 m/s.
  • Scripted vehicles or flight assists can reach 50–100 m/s without difficulty.
  • Modified viewers or physics exploits can push speeds to 200 m/s or higher, especially if the attacker disables simulator limits.

Thus, speeds of 25–100 m/s are commonly sufficient to bypass poorly configured systems, while 100–200 m/s can evade even well-tuned ones with maximum range and minimal intervals.