CariddiCTF/README.md

Cariddi – MCP Client and Server

Complete MCP (Model Context Protocol) stack for CTF and reverse engineering workflows:

---

Cariddi Server

FastMCP server exposing filesystem and execution tools, with correct handling of escape characters when writing Python files.

Setup

cd Cariddi
python3 -m venv venv
source venv/bin/activate   # Windows: venv\Scripts\activate
pip install -r requirements.txt

Run

source venv/bin/activate
python main.py

Server listens on http://0.0.0.0:8000/mcp (streamable HTTP).

Environment

• FASTMCP_HOST / MCP_HOST: host (default 0.0.0.0)
• FASTMCP_PORT / MCP_PORT: port (default 8000)

MCP Inspector

With the server running:

npx @modelcontextprotocol/inspector --url http://localhost:8000/mcp

Use transport Streamable HTTP and URL http://localhost:8000/mcp.

Or run inspector and server together:

npx @modelcontextprotocol/inspector python main.py

With Compose:

docker-compose up -d

Cariddi Client

Python MCP client that talks to Ollama and connects to MCP servers. Configured as a Crypto Solver Agent for CTF crypto challenges.

Requirements

• Python 3.7+
• Ollama installed and running

Install

cd CariddiClient
pip install -r requirements.txt
ollama serve
ollama pull ministral-3   # or llama3.2

Usage

# List models
python mcpClient.py --list-models

# Single prompt
python mcpClient.py --prompt "What is the capital of France?"

# Interactive
python mcpClient.py --interactive

# Custom Ollama and model
python mcpClient.py --base-url http://localhost:11434 --model ministral-3 --prompt "Hello!"

# Connect to MCP server (streamable HTTP)
python mcpClient.py --mcp-server "http://localhost:8000/mcp" --prompt "Use tools to help me"
python mcpClient.py --mcp-server "http://localhost:8000/mcp" --interactive

# With auth headers
python mcpClient.py --mcp-server "http://localhost:8000/mcp" --mcp-headers '{"Authorization": "Bearer token"}' --interactive

Defaults

• Ollama: http://localhost:11434
• Model: ministral-3
• MCP Server: http://localhost:8000/mcp

Crypto Solver Agent

The client is tuned to:

1. Explore: List files (e.g. in /tmp) to find challenge files.
2. Analyze: Recognize crypto (RSA, AES, DES, XOR, encodings) and typical weaknesses.
3. Execute: Write and run Python scripts to recover keys or plaintext.
4. Validate: Look for flags in the form flag{...}.

Covered areas: RSA (small modulus, low exponent, Wiener, Hastad, common modulus), symmetric (AES/DES, ECB/CBC, IV/key reuse), classical ciphers, Base64/Hex/endianness.

CTF Challenges

• cryptoEasy: Diffie–Hellman + AES encryption challenge (in challs/cryptoEasy/).

---

Candidate MCP Servers

Other MCP servers you can combine with Cariddi or use in similar workflows (reverse engineering, binary analysis, malware analysis, shell execution):

Project	Description
radare2-mcp	MCP stdio server for radare2 – binary analysis with r2, r2pipe, optional raw r2 commands.
headless-ida-mcp-server	Headless IDA Pro MCP server – analyze binaries via IDA’s headless mode (idat).
MalwareAnalyzerMCP	MCP server for malware analysis – file, strings, hexdump, objdump, xxd, shell commands with timeouts.
GhidrAssistMCP	Ghidra MCP extension – 34 tools, resources, prompts for reverse engineering (decompile, xrefs, structs, etc.).
shell-exec-mcp	MCP server for shell command execution – run bash commands with optional timeout and background jobs.
ida-pro-mcp	IDA Pro MCP bridge – AI-assisted reversing in IDA (decompile, disasm, xrefs, types, debugger extension).

---