CVE-2026-116684
MEDIUM
MEDIUM
Priority: 0.02
BB Relevance:
54/100
Published: 2026-10-27
Modified: 2026-10-28
First seen: 2026-10-29
Status: active
Attack Surface
Network
No Interaction
Conf. Impact
Integ. Impact
CVSS Vector Breakdown
AV:
Network
AC:
High
PR:
Low
UI:
None
S:
Unchanged
C:
High
I:
High
A:
None
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.