CVE-2026-116684

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.

• CWE-863

• https://github.com/modelcontextprotocol/python-sdk/commit/0c9136841ff092987a20700ff9c2c9789bda2f40
• https://github.com/modelcontextprotocol/python-sdk/commit/8c2fa6eabacde869d75568e33b9d466b58c2f512
• https://github.com/modelcontextprotocol/python-sdk/pull/3447
• https://github.com/modelcontextprotocol/python-sdk/pull/3451
• https://github.com/modelcontextprotocol/python-sdk/releases/tag/v1.30.0
• https://github.com/modelcontextprotocol/python-sdk/releases/tag/v2.2.0
• https://github.com/modelcontextprotocol/python-sdk/security/advisories/GHSA-w4fh-qvv9-3v23

Published

Oct 27, 2026

Last Modified

Oct 28, 2026

Status

Awaiting Analysis

• Uncovering a hidden BOLA in Appsmith's snapshot logicStrix autonomously discovered a BOLA/IDOR vulnerability in Appsmith's snapshot deletion path.
• Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
• PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
• AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.

• CVE-2026-116678Vaultwarden is a Bitwarden-compatible server written in Rust…5.8
• CVE-2026-116679Neko is a a self-hosted virtual browser that runs in Docker …5.4
• CVE-2026-11668Uninitialized Use in Codecs in Google Chrome on Linux, Chrom…4.3
• CVE-2026-116680HomeBox is a home inventory and organization system. Prior t…6.4
• CVE-2026-116682FileBrowser Quantum is a free, self-hosted, web-based file m…8.6
• CVE-2026-116683CTFer.io's CTFd Terraform Provider manages CTFd resources as…7.1
• CVE-2026-116685The Model Context Protocol Python SDK is the official Python…5.9
• CVE-2026-116686The Model Context Protocol Python SDK is the official Python…6.5
• CVE-2026-116687CKEditor 5 is a modern JavaScript rich-text editor with an M…3.1
• CVE-2026-116688CKEditor 5 is a modern JavaScript rich-text editor with an M…8.1
• CVE-2026-116689follow-redirects is a Node.js HTTP and HTTPS client wrapper …5.9
• CVE-2026-11669Out of bounds read in Media in Google Chrome on ChromeOS pri…5.3