arca-agent 0.2.6

ARCA — Local RL-powered Autonomous Cyber Pentesting Agent with LangGraph

ARCA — Autonomous Reinforcement Cyber Agent

A fully local, pip-installable RL-powered cyber pentesting simulation framework with LangGraph orchestration and optional C++ acceleration.

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What is ARCA?

ARCA trains a reinforcement learning agent to autonomously discover and exploit vulnerabilities in simulated computer networks. It combines:

• Gymnasium-compatible environment — realistic hosts, subnets, CVEs, and network topology
• PPO/A2C/DQN via Stable-Baselines3 — policy training with eval callbacks and checkpointing
• LangGraph multi-agent orchestration — Analyst → Attacker → Critic → Reflection pipeline with LLM-powered explanations
• C++ acceleration via pybind11 — BFS reachability, batch exploit simulation, Floyd-Warshall (with pure-Python fallback)
• FastAPI REST interface — /train, /audit, /reflect, /visualize endpoints
• Rich visualization suite — Plotly network graphs, training curves, attack path overlays, vulnerability heatmaps
• Full CLI via Typer: arca train, arca serve, arca audit, arca viz

Everything runs 100% locally — no cloud, no data leaves your machine.

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Installation

Install via PyPI (Recommended)

pip install arca-agent

(Note: If your system has a C++ compiler like g++ or clang, pip will automatically compile the high-performance C++ extensions during installation. Otherwise, it will gracefully fall back to the pure-Python implementation.)

Install from Source (For Development)

git clone https://github.com/dipayandasgupta/arca.git
cd arca

# Create virtual environment
python -m venv venv
source venv/bin/activate       # Windows: venv\Scripts\activate

# Install in editable mode
pip install -e .

# Install with explicit C++ dependencies
pip install -e ".[cpp]"

# Install dev dependencies
pip install -e ".[dev]"

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Quickstart

from arca import ARCAAgent, NetworkEnv, ARCAConfig

# Create environment
env = NetworkEnv.from_preset("small_office")

# Create and train agent
agent = ARCAAgent(env=env)
agent.train(timesteps=50_000)

# Run one episode
result = agent.run_episode(render=True)
print(result.summary())

# LangGraph reflection
agent.enable_langgraph()
report = agent.reflect(env.get_state_dict())
print(report["reflection"])

Or via CLI:

arca train --timesteps 50000 --preset small_office
arca serve                      # starts FastAPI at http://localhost:8000
arca audit --preset enterprise  # one-shot audit report
arca viz --output ./figures     # generate all plots

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Network Presets

Preset	Hosts	Subnets	Vuln Density	Max Steps
small_office	8	2	50%	150
enterprise	25	5	35%	300
dmz	15	3	45%	200
iot_network	20	4	60%	250

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Actions

Action	Description
SCAN	Discover a reachable host and its services/vulns
EXPLOIT	Attempt to compromise a discovered host via a CVE
PIVOT	Move attacker's position to a compromised host
EXFILTRATE	Extract data value from a compromised host

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LangGraph Architecture

START → analyst_node → attacker_node → critic_node → reflect_node → END
                              ↑___________________________|
                                   (reflection loop)

Each node uses a local LLM (via Ollama, default: llama3) for natural-language analysis. Falls back to rule-based logic if Ollama is not running.

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C++ Acceleration

The optional _cpp_sim module (built via pybind11) provides:

• compute_reachability(adj, n) — BFS all-pairs reachability (~10x faster than NetworkX for dense graphs)
• floyd_warshall(weights, n) — All-pairs shortest path
• batch_exploit(hosts, actions, seed) — Vectorised exploit simulation

Falls back to pure Python automatically if not compiled.

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API Endpoints

Once you run arca serve:

Endpoint	Method	Description
/	GET	Health check + status
/train	POST	Start a training run
/audit	POST	Run an audit episode + get report
/reflect	POST	Run LangGraph reflection on state
/status	GET	Current training / agent status
/docs	GET	Auto-generated Swagger UI

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Project Structure

arca/
├── arca/
│   ├── __init__.py          # public API
│   ├── __version__.py
│   ├── cli.py               # Typer CLI
│   ├── core/
│   │   ├── config.py        # ARCAConfig dataclass
│   │   ├── agent.py         # ARCAAgent (PPO wrapper + LangGraph)
│   │   └── trainer.py       # SB3 training harness
│   ├── sim/
│   │   ├── environment.py   # Gymnasium NetworkEnv
│   │   ├── host.py          # Host dataclass
│   │   ├── action.py        # Action / ActionResult types
│   │   └── network_generator.py
│   ├── agents/
│   │   └── langgraph_orchestrator.py
│   ├── cpp_ext/
│   │   ├── __init__.py      # Python fallback + CPP_AVAILABLE flag
│   │   └── sim_engine.cpp   # pybind11 C++ module
│   ├── viz/
│   │   └── visualizer.py    # Plotly + NetworkX charts
│   └── api/
│       └── server.py        # FastAPI app
├── tests/
│   └── test_arca.py
├── examples/
│   └── quickstart.py
├── pyproject.toml
├── setup.py
└── README.md

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Disclaimer

ARCA is a simulation and education tool only. All attack actions run inside a sandboxed in-memory graph. It does not perform any real network scanning, exploitation, or traffic generation. For authorised security testing only.

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Author

Dipayan Dasgupta — IIT Madras, Civil Engineering
GitHub · LinkedIn