Is CVE-2026-116684 being exploited?

No public exploit is currently tracked.

How severe is CVE-2026-116684?

CVE-2026-116684 has a CVSS v3 severity of MEDIUM (6.8).

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CVE-2026-116684

Description

The Model Context Protocol Python SDK is the official Python SDK for Model Context Protocol servers and clients. From 1.10.0 until 1.30.0 and 2.2.0, server-side bearer authentication configured through AuthSettings with token_verifier accepts a valid token issued for another service when the authorization server serves multiple resources and the TokenVerifier does not independently validate the aud audience. This resource-confusion flaw lets a token holder authenticate to the wrong MCP server and exercise that token's resulting access. This issue is fixed in versions 1.30.0 and 2.2.0.