Imported from reason-machines/security-skills (skills/s800-vehicle-network-security-testing/SKILL.md) via skills.sh. Install upstream with npx skills add reason-machines/security-skills --skill s800-vehicle-network-security-testing. Copyright stays with the author.

S800 Vehicle Network Security Testing Framework

Skill by ara.so — Security Skills collection.

Overview

S800 is a vehicle network security testing framework designed for automotive security researchers and penetration testers. It provides tools for analyzing, testing, and securing automotive networks including CAN bus, LIN, FlexRay, and other vehicle communication protocols. The framework enables security assessment of Electronic Control Units (ECUs), protocol fuzzing, traffic analysis, and vulnerability discovery in automotive systems.

Note: This is a testing framework. Only use on vehicles and systems you have explicit authorization to test. Unauthorized vehicle network testing may be illegal and dangerous.

Installation

Prerequisites

• Python 3.7 or higher
• SocketCAN kernel modules (Linux)
• CAN hardware interface (USB-to-CAN adapter, OBD-II dongle, etc.)
• Root/sudo access for network interface configuration

Basic Installation

# Clone the repository
git clone https://github.com/zhu-zhu666/S800-Vehicle-Network-Security-Testing-Framework.git
cd S800-Vehicle-Network-Security-Testing-Framework

# Install Python dependencies
pip install -r requirements.txt

# Install system dependencies (Ubuntu/Debian)
sudo apt-get update
sudo apt-get install can-utils python3-can

Hardware Setup

# Load SocketCAN kernel modules
sudo modprobe can
sudo modprobe can_raw
sudo modprobe vcan

# Setup virtual CAN interface (for testing without hardware)
sudo ip link add dev vcan0 type vcan
sudo ip link set up vcan0

# Setup physical CAN interface (example with slcan)
sudo slcand -o -c -s6 /dev/ttyUSB0 can0
sudo ip link set up can0

# Set CAN bitrate (common automotive: 500kbps)
sudo ip link set can0 type can bitrate 500000

Core Components

1. CAN Bus Analyzer

Capture and analyze CAN bus traffic:

from s800.can_analyzer import CANAnalyzer
from s800.utils import setup_interface

# Initialize analyzer
analyzer = CANAnalyzer(interface='can0')

# Start capturing traffic
analyzer.start_capture(duration=60)  # Capture for 60 seconds

# Analyze captured frames
stats = analyzer.get_statistics()
print(f"Total frames: {stats['total_frames']}")
print(f"Unique IDs: {stats['unique_ids']}")
print(f"Average data rate: {stats['avg_rate']} frames/sec")

# Export captured data
analyzer.export_pcap('capture.pcap')
analyzer.export_csv('capture.csv')

2. Protocol Fuzzer

Fuzz CAN messages to discover vulnerabilities:

from s800.fuzzer import CANFuzzer
from s800.payloads import PayloadGenerator

# Initialize fuzzer
fuzzer = CANFuzzer(interface='can0')

# Define target CAN ID range
target_ids = range(0x100, 0x200)

# Generate mutation-based payloads
payload_gen = PayloadGenerator()
payloads = payload_gen.generate_mutations(
    base_data=[0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07],
    mutation_rate=0.3,
    count=1000
)

# Run fuzzing campaign
fuzzer.fuzz(
    can_ids=target_ids,
    payloads=payloads,
    delay=0.01,  # 10ms between frames
    monitor=True,  # Monitor for anomalies
    callback=lambda result: print(f"Sent: {result}")
)

3. ECU Identification

Identify and fingerprint ECUs on the network:

from s800.ecu_scanner import ECUScanner
from s800.diagnostics import UDSClient

# Scan for active ECUs
scanner = ECUScanner(interface='can0')
ecus = scanner.scan_range(0x700, 0x7FF)

print(f"Found {len(ecus)} ECUs:")
for ecu in ecus:
    print(f"  ID: 0x{ecu['id']:03X}, Type: {ecu['type']}")

# Query ECU information via UDS (ISO 14229)
uds = UDSClient(interface='can0', ecu_id=0x7E0)

# Read DID (Data Identifier)
vin = uds.read_data_by_id(0xF190)  # VIN
print(f"VIN: {vin.decode()}")

# Read diagnostic trouble codes
dtcs = uds.read_dtc()
print(f"Diagnostic Trouble Codes: {dtcs}")

4. Replay Attack

Record and replay CAN traffic:

from s800.replay import CANReplay
import time

# Record session
recorder = CANReplay(interface='can0')
print("Recording traffic... Press Ctrl+C to stop")

try:
    recorder.start_recording()
    time.sleep(30)  # Record for 30 seconds
except KeyboardInterrupt:
    pass

recorder.stop_recording()
recorder.save_session('door_unlock_sequence.s800')

# Replay recorded session
replayer = CANReplay(interface='can0')
replayer.load_session('door_unlock_sequence.s800')

# Replay with original timing
replayer.replay(preserve_timing=True)

# Replay at faster speed
replayer.replay(speed_multiplier=2.0)

# Replay single frame repeatedly
replayer.replay_frame(index=15, count=100, interval=0.05)

5. Man-in-the-Middle

Intercept and modify CAN traffic:

from s800.mitm import CANBridge
from s800.filters import MessageFilter

# Create bridge between two CAN interfaces
bridge = CANBridge(interface_a='can0', interface_b='can1')

# Define filtering rules
def modify_speed(msg):
    """Modify speed data (example: reduce displayed speed)"""
    if msg.arbitration_id == 0x320:  # Speed message ID
        # Modify byte 3-4 (speed value)
        speed = int.from_bytes(msg.data[2:4], byteorder='big')
        new_speed = int(speed * 0.8)  # Reduce by 20%
        msg.data[2:4] = new_speed.to_bytes(2, byteorder='big')
    return msg

# Add filter
bridge.add_filter(modify_speed)

# Block specific messages
bridge.block_id(0x400)  # Block messages with ID 0x400

# Start bridging
bridge.start()

Configuration

Configuration File (config.yaml)

interfaces:
  primary: can0
  secondary: can1
  virtual: vcan0

capture:
  buffer_size: 10000
  auto_save: true
  output_dir: ./captures/

fuzzer:
  default_delay: 0.01
  max_iterations: 10000
  crash_detection: true
  anomaly_threshold: 5.0

scanner:
  timeout: 1.0
  retry_count: 3
  id_range:
    start: 0x000
    end: 0x7FF

uds:
  default_timeout: 2.0
  session_type: extended  # default, extended, programming
  security_access: false

logging:
  level: INFO
  file: s800.log
  console: true

Load configuration:

from s800.config import Config

config = Config.load('config.yaml')
analyzer = CANAnalyzer(
    interface=config.interfaces['primary'],
    buffer_size=config.capture['buffer_size']
)

Advanced Usage

Custom Protocol Analysis

from s800.protocols import ProtocolDecoder

class CustomProtocolDecoder(ProtocolDecoder):
    """Decode proprietary protocol"""
    
    def decode(self, msg):
        if msg.arbitration_id == 0x300:
            return {
                'type': 'sensor_data',
                'temperature': msg.data[0] - 40,  # Offset by 40
                'pressure': int.from_bytes(msg.data[1:3], 'big') / 10,
                'status': msg.data[3]
            }
        return None

# Use custom decoder
analyzer = CANAnalyzer(interface='can0')
analyzer.add_decoder(CustomProtocolDecoder())
analyzer.start_capture()

Anomaly Detection

from s800.ml import AnomalyDetector

# Train baseline model
detector = AnomalyDetector()
detector.train_from_pcap('normal_traffic.pcap')

# Real-time anomaly detection
analyzer = CANAnalyzer(interface='can0')

def check_anomaly(msg):
    if detector.is_anomaly(msg):
        print(f"ANOMALY DETECTED: ID=0x{msg.arbitration_id:03X}")
        print(f"  Data: {msg.data.hex()}")
        # Take action (log, alert, block, etc.)

analyzer.add_callback(check_anomaly)
analyzer.start_capture()

Automated Security Assessment

from s800.assessment import SecurityAssessment

# Run comprehensive security assessment
assessment = SecurityAssessment(interface='can0')

results = assessment.run_all_tests(
    tests=[
        'ecu_discovery',
        'uds_services',
        'authentication_bypass',
        'replay_protection',
        'fuzzing_resilience'
    ],
    report_format='html'
)

assessment.save_report('security_report.html')
print(f"Assessment complete. Score: {results['security_score']}/100")

CLI Commands

Basic Commands

# Capture CAN traffic
python s800.py capture -i can0 -d 60 -o capture.pcap

# Scan for ECUs
python s800.py scan -i can0 --range 0x700-0x7FF

# Fuzz CAN IDs
python s800.py fuzz -i can0 --ids 0x100-0x200 --count 1000

# Replay traffic
python s800.py replay -i can0 -f capture.pcap --speed 1.0

# UDS diagnostics
python s800.py uds -i can0 --ecu 0x7E0 --read-vin

# Run security assessment
python s800.py assess -i can0 --output report.html

Advanced Commands

# MITM with filtering
python s800.py mitm -a can0 -b can1 --block 0x400 --modify speed_reducer.py

# Export analysis
python s800.py analyze -f capture.pcap --export csv --stats

# Differential analysis
python s800.py diff baseline.pcap test.pcap --threshold 0.05

Environment Variables

# Default CAN interface
export S800_INTERFACE=can0

# Configuration file path
export S800_CONFIG=/etc/s800/config.yaml

# Output directory
export S800_OUTPUT_DIR=/var/log/s800/

# Debug mode
export S800_DEBUG=1

# API endpoint (if using remote analysis)
export S800_API_URL=https://analysis.example.com
export S800_API_KEY=your_api_key_here

Common Patterns

Pattern 1: Pre-Test Baseline Capture

# Always capture baseline before testing
baseline = CANAnalyzer(interface='can0')
baseline.start_capture(duration=300)  # 5 minutes
baseline.save('baseline.pcap')

# Run tests
# ...

# Compare with baseline
test_capture = CANAnalyzer(interface='can0')
test_capture.start_capture(duration=60)
diff = test_capture.compare_with('baseline.pcap')
print(f"New messages: {diff['new_ids']}")

Pattern 2: Safe Fuzzing

# Monitor system health during fuzzing
from s800.monitoring import SystemMonitor

monitor = SystemMonitor(interface='can0')
fuzzer = CANFuzzer(interface='can0')

monitor.add_safety_check('ecu_response', timeout=5.0)
monitor.add_safety_check('error_frames', threshold=10)

fuzzer.set_safety_monitor(monitor)
fuzzer.fuzz(can_ids=[0x100], payloads=payloads, emergency_stop=True)

Troubleshooting

CAN Interface Not Found

# Check interface status
ip link show can0

# Verify kernel modules
lsmod | grep can

# Check dmesg for errors
dmesg | grep can

Permission Denied

# Add user to dialout group (for USB devices)
sudo usermod -a -G dialout $USER

# Run with sudo (temporary)
sudo python s800.py capture -i can0

No Traffic Received

# Verify bitrate matches vehicle
sudo ip link set can0 type can bitrate 500000

# Check for bus-off state
candump can0 -e  # Show error frames

# Test with cansend
cansend can0 123#DEADBEEF

High Bus Load

# Limit capture rate
analyzer = CANAnalyzer(interface='can0', filter_ids=[0x100, 0x200])

# Use hardware filtering if available
analyzer.set_hardware_filter(mask=0x700, match=0x300)

Safety and Legal Warnings

• Only test systems you own or have written authorization to test
• Never test on public roads or active vehicles
• Automotive systems control safety-critical functions
• Improper testing can cause vehicle damage or safety hazards
• Always have emergency stop procedures in place
• Consult legal counsel before testing automotive systems

Resources

• Repository: https://github.com/zhu-zhu666/S800-Vehicle-Network-Security-Testing-Framework
• CAN Bus Specification: ISO 11898
• UDS Protocol: ISO 14229
• Automotive Ethernet: IEEE 802.1
• SocketCAN Documentation: https://www.kernel.org/doc/html/latest/networking/can.html