MCP TypeScript SDK OAuth Client Credential Exposure Vulnerability

# MCP TypeScript SDK OAuth Client Credential Exposure Vulnerability

https://gcdradar.vercel.app/incidents/mcp-typescript-sdk-oauth-client-credential-exposure-vulnerab · AIR-2026-0251 · closed 2026-10-06

- Lane: Patch now
- Severity: 2 (Disclosed vulnerability)
- Fix status: Fix status unknown
- First reported: 2026-10-06
- AI role: Attack on AI
- Products: MCP TypeScript SDK
- CVE ids: CVE-2026-104850
- CVSS: 7.5

## Summary

An OAuth client flaw in the MCP TypeScript SDK allowed a compromised MCP server to direct OAuth credentials to an arbitrary authorization server. Users were advised to update their applications to secure the SDK.

## What to do

No action recorded; read the sources below and the vendor's advisory.

## Latest updates

- 2026-10-06: CVE-2026-104850: MCP TypeScript SDK is the official TypeScript SDK for Model Context Protocol servers and clients. (https://nvd.nist.gov/vuln/detail/CVE-2026-104850)
- 2026-10-06: CVE-2026-104850: MCP TypeScript SDK: OAuth client could send credentials to an authorization server chosen by the MCP server (https://github.com/advisories/GHSA-6qxp-vccf-f47h)

## Sources

- 2026-10-06 GitHub Advisory Database: CVE-2026-104850: MCP TypeScript SDK: OAuth client could send credentials to an authorization server chosen by the MCP server https://github.com/advisories/GHSA-6qxp-vccf-f47h
- 2026-10-06 NVD: CVE-2026-104850: MCP TypeScript SDK is the official TypeScript SDK for Model Context Protocol servers and clients. https://nvd.nist.gov/vuln/detail/CVE-2026-104850

Verify against the vendor's advisory before changing production. Data CC BY-SA 4.0, https://gcdradar.vercel.app.