EUVD-2026-93491Published

MCP TypeScript SDK is the official TypeScript SDK for Model Context Protocol servers and clients. Starting in version 1.12.0 and prior to versions 1.31.0 and 2.2.0, the SDK's OAuth client support let the MCP server a client connected to dec…

Exact source revision recorded 11 Nov 2026 05:30:29 UTC. It does not establish the source's current position. Latest evidence.

Recorded JSON

euvd · EUVD-2026-93491

Published

MCP TypeScript SDK is the official TypeScript SDK for Model Context Protocol servers and clients. Starting in version 1.12.0 and prior to versions 1.31.0 and 2.2.0, the SDK's OAuth client support let the MCP server a client connected to decide which authorization server received the client's OAuth credentials. Stored and pre-provisioned credentials were not bound to the authorization server they belong to. A malicious or compromised MCP server could name its own authorization server in its protected resource metadata. Without any user interaction, the client would send that server the `refresh_token` and `client_secret` stored from an earlier sign-in (1.x), or the configured `client_secret` or signed assertion of a bundled non-interactive provider (1.x and 2.x). Only those applications that use the SDK as an MCP client over HTTP with an `authProvider`: your own `OAuthClientProvider`, or the bundled `ClientCredentialsProvider`, `PrivateKeyJwtProvider`, `StaticPrivateKeyJwtProvider` or (2.x) `CrossAppAccessProvider` and that may connect to an MCP server the owners does not fully trust while holding credentials for a legitimate authorization server are affected. `@modelcontextprotocol/sdk` 1.31.0 (1.x) and `@modelcontextprotocol/client` 2.2.0 (2.x) patch the issue. A workaround for those who cannot upgrade is available. 2.0.0 and 2.1.0 already accept `expectedIssuer`. On 1.x, the only workaround is to connect OAuth-enabled clients only to MCP servers you trust.

EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.

Original publisher date fields

datePublished: Oct 6, 2026, 4:08:21 PM

dateUpdated: Oct 6, 2026, 4:28:53 PM

1 related source bulletins · separate from aliases

WID-SEC-W-2026-4410: IBM App Connect Enterprise: Mehrere Schwachstellen

CVE-2026-100699 · CVE-2026-100700 · CVE-2026-100701 · CVE-2026-100702 · CVE-2026-101898 · CVE-2026-101900 · CVE-2026-101901 · CVE-2026-101902 · CVE-2026-101903 · CVE-2026-101904 · CVE-2026-101905 · CVE-2026-101906 · CVE-2026-101907 · CVE-2026-101908 · CVE-2026-101909 · CVE-2026-101915 · CVE-2026-101916 · CVE-2026-104850 · CVE-2026-106444 · CVE-2026-106445 · CVE-2026-106446 · CVE-2026-110869 · CVE-2026-111767 · CVE-2026-15187 · CVE-2026-33937 · CVE-2026-83745 · CVE-2026-84003 · CVE-2026-86535 · CVE-2026-90776 · CVE-2026-91863 · CVE-2026-91864 · CVE-2026-91865 · CVE-2026-91866 · CVE-2026-91867 · CVE-2026-93687 · CVE-2026-93749 · CVE-2026-94645 · CVE-2026-94646 · CVE-2026-96294

Source published: Oct 6, 2026, 4:08:21 PM (timezone not stated)
Source modified: Oct 6, 2026, 4:28:53 PM (timezone not stated)
Observed here: 11 Nov 2026 05:30:29 UTC
Source terms: ENISA EUVD · source terms and attribution apply

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: euvd · ENISA EUVD · source terms and attribution apply. Source text is retained; field grouping and change labels are provided by ChangeIntel.

EUVD CVSS 3.1 · 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N