9,400 MCP Servers Later, Only 8.5% Use OAuth

The public MCP server registry grew from roughly 1,200 servers in the first quarter of 2025 to more than 9,400 by mid-April 2026, a sevenfold increase in fourteen months. Authentication practices did not grow with it.

A security audit covered by Microsoft's Tech Community found that 25% of public MCP servers run with zero authentication at all. Another 53% rely on long-lived static API keys or personal access tokens, credentials that don't expire on their own and keep working long after the task they were issued for is finished. Only 8.5% use OAuth, the standard that actually supports scoped, revocable access.

Of the servers that do use keys, 79% pass those credentials through environment variables, according to Practical DevSecOps' MCP Security Statistics 2026 Report, a pattern that makes the key visible to anything else with access to the process environment, including any other tool the same agent happens to invoke in the same session.

The adoption side of this is already showing up as friction: 38% of organizations cite security concerns as an active blocker on their own MCP rollout plans, not a hypothetical future risk. Given that three quarters of public servers skip real authentication entirely, that hesitation looks less like caution and more like an accurate read of what's actually out there.