MCP Defender

mcp-name: io.github.trickyfalcon/mcp-msdefenderkql
An MCP (Model Context Protocol) server for Microsoft Defender Advanced Hunting. Enables AI assistants to investigate security events using natural language by translating queries to KQL and executing them against Defender.
How It Works
User: "Show me suspicious PowerShell activity in the last hour"
↓
AI translates to KQL using schema knowledge
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MCP executes query against Defender API
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AI interprets and explains the results
Features
- Advanced Hunting: Execute KQL queries against Defender's Advanced Hunting API
- Dynamic Schema Discovery: Fetch available tables and columns directly from your Defender instance
- Natural Language Security Investigations: Let AI translate your questions into KQL
- Certificate Authentication: Secure authentication using Azure AD certificates (recommended)
Prerequisites
- Python 3.10+
- Azure AD App Registration with WindowsDefenderATP permission:
AdvancedQuery.Read.All - Run advanced queries
Installation
From PyPI (Recommended)
pip install mcp-msdefenderkql
From Source
git clone https://github.com/trickyfalcon/mcp-defender.git
cd mcp-defender
python -m venv .venv
source .venv/bin/activate
pip install -e ".[dev]"
Configuration
- Copy
.env.example to .env
- Fill in your Azure AD credentials:
AZURE_TENANT_ID=your-tenant-id
AZURE_CLIENT_ID=your-client-id
AZURE_CLIENT_CERTIFICATE_PATH=/path/to/combined.pem
Certificate Setup
For certificate authentication, combine your private key and certificate:
cat private.key cert.pem > combined.pem
Usage
Running the Server
mcp-msdefenderkql
Testing with MCP Inspector
npx @modelcontextprotocol/inspector mcp-msdefenderkql
Claude Desktop Configuration
Add to your Claude Desktop config (~/Library/Application Support/Claude/claude_desktop_config.json):
{
"mcpServers": {
"defender": {
"command": "/path/to/mcp-defender/.venv/bin/python",
"args": ["-m", "mcp_defender.server"],
"env": {
"PYTHONPATH": "/path/to/mcp-defender/src",
"AZURE_TENANT_ID": "your-tenant-id",
"AZURE_CLIENT_ID": "your-client-id",
"AZURE_CLIENT_CERTIFICATE_PATH": "/path/to/combined.pem"
}
}
}
}
Available Tools
run_hunting_query | Execute KQL queries against Advanced Hunting |
get_hunting_schema | Get available tables and columns dynamically |
Example Natural Language Queries
Once connected to Claude, you can ask:
- "Show me any suspicious PowerShell activity in the last hour"
- "Find devices with failed login attempts"
- "What processes are making network connections to external IPs?"
- "List all devices that haven't checked in for 7 days"
Example KQL Queries
// Find failed logon attempts
DeviceLogonEvents
| where ActionType == "LogonFailed"
| where Timestamp > ago(24h)
| summarize FailedAttempts = count() by AccountName, DeviceName
| top 10 by FailedAttempts
// Detect suspicious PowerShell
DeviceProcessEvents
| where FileName in~ ("powershell.exe", "pwsh.exe")
| where ProcessCommandLine has_any ("encodedcommand", "bypass", "hidden", "downloadstring")
| project Timestamp, DeviceName, AccountName, ProcessCommandLine
// Network connections to external IPs
DeviceNetworkEvents
| where RemoteIPType == "Public"
| where Timestamp > ago(1h)
| summarize ConnectionCount = count() by DeviceName, RemoteIP
| top 20 by ConnectionCount
Development
pytest
ruff check .
mypy src
bandit -r src
API Reference
This server uses the unified Microsoft 365 Defender API:
- Endpoint:
https://api.security.microsoft.com
- Advanced Hunting:
POST /api/advancedqueries/run
License
MIT