MCP Security Analyst

A Model Context Protocol (MCP) server providing comprehensive security analysis capabilities through integration with OSV.dev vulnerability database and native Go-based code analysis and secret detection engines.

Features

• Supply Chain Vulnerability Analysis: Integration with OSV.dev API for dependency vulnerability assessment
• Secret Detection: Gitleaks v8 integration with 100+ built-in detection rules for credentials and API keys
• Static Code Analysis: AST-based Go code analysis for security anti-patterns
• Pattern Matching: Regex-based detection for common security vulnerabilities
• MCP Protocol Support: Standard protocol implementation for AI assistant integration
• Community-Vetted Rules: Gitleaks patterns maintained by the security community

Requirements

Core Requirements

make deps
make install

Build Dependencies

• Go 1.25.4 or later
• github.com/mark3labs/mcp-go
• github.com/zricethezav/gitleaks/v8

Installation

make deps     # Install Go module dependencies
make build    # Compile binary
make install  # Install to /usr/local/bin
make run       # Build and execute server
make clean     # Remove build artifacts

pre-built releases

The mcp-osv binary communicates via stdin/stdout using the MCP protocol.

IDE Configuration

Cursor IDE

Navigate to Configuration > MCP and add:

{
  "mcpServers": {
    "security_analyst": {
      "name": "Security Analyst",
      "type": "stdio",
      "command": "/usr/local/bin/mcp-osv"
    }
  }
}

Claude Desktop

Edit the MCP configuration file at Settings > Developer:

{
  "mcpServers": {
    "mcp_osv": {
      "command": "/usr/local/bin/mcp-osv",
      "args": []
    }
  }
}

Available Tools

The server exposes three MCP tools for security analysis:

check_vulnerabilities

Query OSV.dev database for known vulnerabilities in specific package versions.

Parameters:

• package_name (string, required): Package identifier
• version (string, required): Version string

Functionality:

• Rate-limited API requests (1 request/second)
• HTTP timeout protection (10 seconds)
• JSON response parsing
• Vulnerability detail extraction

analyze_security

Comprehensive security analysis combining multiple detection engines.

Parameters:

• file_path (string, required): Target file or directory path

Analysis Components:

• Native Go AST-based code analysis
• Gitleaks v8 secret detection with 100+ rules
• OSV.dev vulnerability checks for dependencies (go.mod files)
• Pattern-based vulnerability detection

Detected Issues:

• Command injection vectors
• Deserialization vulnerabilities
• SQL injection patterns
• Hardcoded credentials
• API keys and tokens
• Private keys and certificates
• Database connection strings

scan_secrets

Dedicated secret detection using Gitleaks v8 with 100+ community-maintained detection rules.

Parameters:

• path (string, required): Target file, directory, or repository path
• scan_git_history (boolean, optional): Enable git history scanning (default: false)

Detection Capabilities (100+ patterns):

• AWS Access Keys, Secret Keys, Session Tokens
• GitHub Personal Access Tokens, OAuth tokens
• Google Cloud Platform API keys
• Azure credentials and connection strings
• Slack tokens and webhooks
• Stripe API keys
• Private SSH/PGP/RSA keys
• JWT tokens
• Database connection strings (PostgreSQL, MySQL, MongoDB)
• Generic API keys with entropy analysis
• And 90+ more patterns maintained by the security community

Output: Partial secret redaction for secure display (first 4 + last 4 characters)

Integration Patterns

The MCP server enables AI assistants to perform security analysis through natural language requests:

Dependency Vulnerability Scanning:

Request: "Check dependencies in go.mod for vulnerabilities"
Tool Execution: analyze_security -> OSV.dev API queries
Response: Vulnerability report with CVE details

Secret Detection:

Request: "Scan repository for exposed credentials"
Tool Execution: scan_secrets -> Pattern matching + entropy analysis
Response: Detected secrets with file locations and types

Comprehensive Audit:

Request: "Perform full security analysis"
Tool Execution: analyze_security -> All detection engines
Response: Combined report (code issues + secrets + vulnerabilities)

Security Implementation Details

Rate Limiting

OSV.dev API requests are rate-limited at 1 request per second using golang.org/x/time/rate limiter to prevent service throttling.

Input Validation

All file paths undergo sanitization to prevent directory traversal attacks:

• Path cleaning via filepath.Clean()
• Directory traversal pattern detection
• Existence verification

Secret Redaction

Detected secrets are partially redacted before display:

• Secrets <= 8 characters: Full redaction
• Secrets > 8 characters: First 4 + "***" + Last 4 characters

Gitleaks Integration

Secret detection powered by Gitleaks v8:

• 100+ community-maintained detection rules
• Entropy analysis for high-randomness strings
• Keyword-based pre-filtering for performance
• Regular updates for new secret types

Adding Security Rules

To extend detection capabilities:

1. Secrets and credential detection: Gitleaks rules are maintained upstream at gitleaks/gitleaks
2. Code Analysis: Extend AST inspection in runGoCodeAnalysis()
3. Pattern Matching: Regex patterns can be added to analyzeFile() checks map, create a branch and PR explaining them to get merged

License

MIT