MCP authorization: OAuth and PKCE for remote MCP servers
ATR evaluates whether remote authorization follows the expected OAuth and PKCE protections.
Why it matters
Agent-specific protocol risks matter. For example, a local MCP server that does not validate the requesting origin and host may be exposed to DNS rebinding.
In the registry
ATR evaluated this on 16 MCP servers in the 20 published reports, as of Nov. 9th, 2026, and found an issue in 11, across 10 reports.
Each report shows the exact file and lines, why the issue matters, and the recommended fix, with a fix prompt you can paste into your coding agent. Browse the reports.
Questions
What does ATR check for mCP authorization?
ATR evaluates whether remote authorization follows the expected OAuth and PKCE protections. Each MCP server is assessed against 26 rules: 14 common, one guardrail, and 11 MCP-specific rules.
Why does mCP authorization matter?
Agent-specific protocol risks matter. For example, a local MCP server that does not validate the requesting origin and host may be exposed to DNS rebinding.
How often does the registry find it?
ATR evaluated this on 16 MCP servers in the 20 published reports, as of Nov. 9th, 2026, and found an issue in 11, across 10 reports.
How do I check my own MCP server?
Request a scan at bluerock.io/scan. Your first scan is free. Each MCP server is assessed against 26 rules: 14 common, one guardrail, and 11 MCP-specific rules.
Source: BlueRock, Component Level Security Analysis for MCP Servers, Agent Skills and Plugins (Oct. 22nd, 2026).