I Scanned 706 MCP Servers — 30% Had No Authentication

I run an automated security scanner for MCP (Model Context Protocol) servers — the new standard for connecting AI assistants to external tools. The Numbers After scanning 706 MCP servers : 30% had no authentication — anyone could access their tools 47% had at least one high-severity issue Common vulnerabilities: auth bypass, prompt injection vectors, data exfiltration through error messages Why This Matters MCP servers give AI assistants access to databases, APIs, file systems, and more. A vulnerability in an MCP server means an attacker can: Read your data through tools meant for the AI Execute actions (create records, send emails, delete files) Inject prompts that make the AI do unintended things Most Common Issues 1. No Authentication (30%) Tools accessible without any credentials. If your MCP server is on the internet, anyone can use it. 2. No Rate Limiting (45%) Endpoints accept unlimited requests. Trivial to DoS. 3. Dangerous Tools Without Confirmation Tools that can delete data,