dev.to· Oct 3, 2026· by jeff_pdc

MCP Authentication Explained: OAuth 2.1 for Remote MCP Servers

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A local MCP server launched over stdio inherits whatever credentials are already on your machine....
🎯 Vulnerability: OAuth 2.0 / JWT Authentication Bypass
💡 Defense Fix: Strictly verify JWT signatures on the backend, enforce state parameter validation, and reject 'alg: none'.
#mcp#oauth#security#ai