Bug 2562339 (CVE-2026-116684) - CVE-2026-116684 mcp: mcp: Authentication bypass via missing token audience validation
Summary: CVE-2026-116684 mcp: mcp: Authentication bypass via missing token audience va...
Keywords:
Status: NEW
Alias: CVE-2026-116684
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
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Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-10-27 19:22 UTC by OSIDB Bzimport
Modified: 2026-10-31 08:31 UTC (History)
55 users (show)

Fixed In Version:
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Description OSIDB Bzimport 2026-10-27 19:22:00 UTC 
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.
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