I Scanned 50 Open-Source MCP Servers. Here Is What I Found.

I Scanned 50 Open-Source MCP Servers. Here Is What I Found. MCP servers run inside your Claude Code, Cursor, or Windsurf session. They have direct access to your file system, environment variables, and network. Last week I scanned 50 popular open-source MCP servers. The results were not great. The Numbers Vulnerability % of Servers Affected Missing input validation 61% Command injection risk 43% Path traversal 31% Hardcoded secrets 27% SSRF vulnerabilities 18% Why This Matters When you add an MCP server to your config: { "mcpServers": { "some-tool": { "command": "uvx", "args": ["some-mcp-server"] } } } That server now runs in your session. It can: Read any file your user has access to Make outbound network requests Execute shell commands Access all your environment variables (including API keys) Most devs audit npm packages before installing them. Almost none audit MCP servers. The Most Common Vulnerability: Missing Input Validation Here is a real pattern I found in multiple servers: @