Open-Source Security · oritera

Cairn

Cairn is a Python-based AI agent system that solves problems by searching through unknown state spaces, validated first on autonomous penetration testing. It uses a blackboard architecture where multiple AI workers coordinate asynchronously to explore intents and build up facts toward a goal, with support for Claude, Codex, and Pi backends.

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Source: GitHub — github.com/oritera/Cairn

1.9k

GitHub stars

269

Forks

Python

Primary language

AGPL-3.0

License (OSI-approved)

Key facts

Objective fields from the source. Values we can't verify are shown as “Unknown” rather than guessed.

Field	Value
Repository	oritera/Cairn
Owner	oritera
Primary language	Python
License	AGPL-3.0 — OSI-approved
Stars	1.9k
Forks	269
Open issues	4
Latest release	v0.2.1 (2026-05-10)
Last updated	2026-06-30
Source	https://github.com/oritera/Cairn

What Cairn is

Cairn implements a stigmergy-based OODA loop architecture where stateless agent workers read a shared fact-intent graph, reason about next steps, and write findings back without direct coordination. The dispatcher schedules tasks across containerized workers; the server maintains graph consistency. Requires Python ≥3.12, Docker, and external LLM endpoints.

Quickstart

Get the Cairn source

Clone the repository and explore it locally.

terminalbash

1git clone https://github.com/oritera/Cairn.git2cd Cairn3# follow the project's README for install & configuration

Need it deployed, integrated, or customized instead? DEV.co ships production installs.

Best use cases

Authorized Penetration Testing & CTF Challenges

Cairn was designed and validated on autonomous penetration testing (54/54 problems solved in Tencent hackathon). It excels at directed exploration with a clear origin and goal in partially-known environments.

Security Research & Vulnerability Assessment

The state-space search model fits vulnerability discovery workflows where the path forward is unknown but the success condition is measurable. Multi-agent exploration can cover wider ground than sequential tools.

General Problem-Solving with LLM Agents

Beyond security, Cairn's blackboard model applies to mathematical proofs, puzzle solving, and any domain with an origin, goal, and unknown search path. The architecture is not domain-specific.

Implementation considerations

Requires valid API credentials for Claude, Codex, or Pi endpoints in dispatch.yaml. Dependent on third-party LLM availability and rate limits.
Agent workers run in Docker containers; containerized workloads for the target domain (e.g., network scanners, exploit tools) must be layered on top. Core engine does not include security tools.
Graph consistency is server-side only. Dispatcher is single-threaded bottleneck for task scheduling; horizontal scaling story is unclear.
Worker prompt engineering and task generation happen at runtime from graph state. Behavior is emergent and may be difficult to audit, debug, or reproduce for sensitive use cases.
Python 3.12+ and uv package manager required. Development group dependencies needed for tests; production footprint unknown.

When to avoid it — and what to weigh

Requires AGPL Compliance in Proprietary Products — Licensed under AGPL-3.0. Using in closed-source commercial software obligates open-source release of modifications or requires purchasing a commercial license from authors.
Need Offline or Air-Gapped Deployment — Requires real-time calls to external LLM endpoints (Claude, Codex, Pi). No local model fallback is documented. Cannot run in disconnected environments.
Require Production SLA & Stability Guarantees — Project is young (created April 2026, latest release May 2026). Limited real-world production track record outside the hackathon validation. Architectural maturity and failure modes unknown.
Operating on Systems Without Explicit Authorization — README contains explicit disclaimer: unauthorized use against systems/networks without owner permission may be illegal. Operators must ensure legal compliance independently.

License & commercial use

Cairn is licensed under GNU AGPLv3. For personal and educational use, it is free. Any modifications or network-accessible derivatives must release source code under AGPL-3.0. This applies equally to internal tools that are shared across an organization.

AGPL-3.0 is a copyleft license. Incorporating Cairn into a closed-source commercial product, SaaS offering, or internal-use-only proprietary tool will trigger AGPL obligations (source code disclosure) or require a separate commercial license from the authors. The README explicitly invites commercial licensing inquiries. Obtain legal review before integrating into any non-trivial commercial stack.

DEV.co evaluation signals

Editorial assessment — not user reviews. Directional, with an explicit confidence level.

Signal	Assessment
Maintenance	Active
Documentation	Adequate
License clarity	Clear
Deployment complexity	High
DEV.co fit	Possible
Assessment confidence	Medium

Security considerations

Cairn is a tool designed for authorized security testing. Operators must enforce authorization controls independently; the tool does not validate target legitimacy. Agents execute code and network calls via containers; isolation depends on Docker/container runtime security. LLM prompt injection and agent hallucination are not addressed in documentation. Graph is stored locally; no encryption at rest or in transit is documented. Use only in authorized, controlled environments with explicit permission.

Alternatives to consider

Metasploit / Nuclei

Established penetration testing frameworks with predefined modules, extensive docs, and no LLM dependency. Better for known vulnerabilities; less suitable for novel exploration.

OpenAI / Anthropic Agent Frameworks (e.g., Autogen, LangChain agents)

General-purpose LLM agent libraries with broader ecosystem, more documentation, and commercial support. Cairn's blackboard architecture is more specialized; LLM frameworks are more flexible but less structured for state-space search.

OWASP ZAP / Burp Suite

Mature, feature-complete web security tools with GUIs and professional support. Rules-based, not AI-driven. Better for known attack patterns; no autonomous exploration.

Software development agency

Build on Cairn with DEV.co software developers

If you're considering Cairn for security testing or custom AI agent workflows, schedule a consultation with our engineers. We can help you evaluate integration complexity, license strategy, and commercial terms.

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Cairn FAQ

Can I use Cairn commercially?

Not without a commercial license. AGPL-3.0 requires either open-sourcing derivatives or obtaining a separate license from the authors. Contact details are in the README.

Does Cairn include built-in pentesting tools (scanners, exploits)?

No. Cairn is an orchestration engine. Security tools (Nmap, Metasploit, etc.) must be containerized and integrated separately by operators.

What LLMs does Cairn support?

Claude, Codex, and Pi. Requires valid API credentials. No local models, no open-weight LLM integration is documented.

Is Cairn production-ready?

Unknown. It passed a hackathon but was deployed for the first time at race time. Stability, scalability, and production operational patterns are not established. Treat as experimental.

Custom software development services

DEV.co is a software development agency delivering custom software development services to companies building on open source. Our software developers and web developers design, integrate, and ship production systems — spanning web development, APIs, AI, data, and cloud. If Cairn is part of your open-source security roadmap, our team can implement, customize, migrate, and maintain it.

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