{"id":"EUVD-2026-93491","revision":null,"records":[{"revision":"d904b47ae12f47e1bf917944d737fb72","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-104850","aliases":[],"title":"MCP TypeScript SDK: OAuth client could send credentials to an authorization server chosen by the MCP server","description":"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.","state":0,"publishedAt":"2026-10-06T16:08:21.514+00:00","modifiedAt":"2026-10-06T16:28:53.097+00:00","affected":[{"ecosystem":"Vendor product","name":"typescript-sdk","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"modelcontextprotocol\",\n                    \"product\": \"typescript-sdk\",\n                    \"versions\": [\n                        {\n                            \"version\": \">= 1.12.0, < 1.31.0\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \">= 2.0.0, < 2.2.0\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","score":7.5,"severity":"HIGH"}],"references":["https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-6qxp-vccf-f47h","https://github.com/modelcontextprotocol/typescript-sdk/pull/2887","https://github.com/modelcontextprotocol/typescript-sdk/commit/edd12e282620ebf770d67316f19cf91d4112a1bd","https://github.com/modelcontextprotocol/typescript-sdk/releases/tag/v2.2.0"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-104850","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-104850","identifiers":["CVE-2026-104850"]},"retained":false,"historicalAffected":[]},{"revision":"d5aad892dfb441a6bee5b5d861d075a6","observedAt":"2026-11-11T05:30:29.275+00:00","statement":{"source":"euvd","id":"EUVD-2026-93491","aliases":["CVE-2026-104850","GHSA-6qxp-vccf-f47h"],"title":"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…","description":"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.","state":0,"publishedAt":null,"modifiedAt":null,"affected":[],"metrics":[{"system":"EUVD CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","score":7.5,"severity":null}],"references":["https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-6qxp-vccf-f47h","https://github.com/modelcontextprotocol/typescript-sdk/pull/2887","https://github.com/modelcontextprotocol/typescript-sdk/commit/edd12e282620ebf770d67316f19cf91d4112a1bd","https://github.com/modelcontextprotocol/typescript-sdk/releases/tag/v2.2.0"],"sourceUrl":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-93491","license":"ENISA EUVD · source terms and attribution apply","enrichment":{"sourceStatus":null,"weaknesses":[],"productCriteria":[],"sourceDates":{"datePublished":"Oct 6, 2026, 4:08:21 PM","dateUpdated":"Oct 6, 2026, 4:28:53 PM"},"relatedAdvisories":[{"id":"WID-SEC-W-2026-4410","title":"IBM App Connect Enterprise: Mehrere Schwachstellen","vulnerabilityIds":["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"]}],"note":"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."},"key":"euvd:EUVD-2026-93491","identifiers":["EUVD-2026-93491","CVE-2026-104850","GHSA-6qxp-vccf-f47h"]},"retained":false,"historicalAffected":[]},{"revision":"6d29cc4777fe4c228095bf1236d0129d","observedAt":"2026-10-25T04:17:29.458+00:00","statement":{"source":"nvd","id":"CVE-2026-104850","aliases":[],"title":"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…","description":"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.","state":0,"publishedAt":"2026-10-06T17:17:15.827+00:00","modifiedAt":"2026-10-06T20:03:40.69+00:00","affected":[],"metrics":[{"system":"CVSS 3.1 · security-advisories@github.com · Secondary","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","score":7.5,"severity":"HIGH"}],"references":["https://github.com/modelcontextprotocol/typescript-sdk/commit/edd12e282620ebf770d67316f19cf91d4112a1bd","https://github.com/modelcontextprotocol/typescript-sdk/pull/2887","https://github.com/modelcontextprotocol/typescript-sdk/releases/tag/v2.2.0","https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-6qxp-vccf-f47h"],"sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-104850","license":"NIST NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Awaiting Analysis","weaknesses":["CWE-345","CWE-522"],"productCriteria":[],"sourceDates":{"published":"2026-10-06T17:17:15.827","lastModified":"2026-10-06T20:03:40.690"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON."},"key":"nvd:CVE-2026-104850","identifiers":["CVE-2026-104850"]},"retained":false,"historicalAffected":[]},{"revision":"961d0e482fe44991ae02d55d3dd0ec14","observedAt":"2026-10-24T13:17:17.793+00:00","statement":{"source":"osv","id":"GHSA-6qxp-vccf-f47h","aliases":["CVE-2026-104850"],"title":"MCP TypeScript SDK: OAuth client could send credentials to an authorization server chosen by the MCP server","description":"### Summary\nIn affected versions, the SDK's OAuth client let the MCP server decide which authorization server received the client's OAuth credentials. Credentials were not tied to the authorization server they belong to.\n\nA malicious or compromised MCP server could name its own authorization server. With no user interaction, the client would send it:\n\n- the `refresh_token` and `client_secret` stored from an earlier sign-in\n- the `client_secret` or signed assertion configured on a bundled provider\n\n### Am I affected?\nYes, if both of these hold:\n\n- your application uses the SDK's OAuth client over HTTP, through any of:\n    - an `authProvider` on a transport\n    - the `withOAuth()` middleware\n    - direct calls to `auth()` or `fetchToken()`\n- it may connect to an MCP server you do not fully trust while holding credentials for a legitimate authorization server\n\nAffected versions:\n\n- `@modelcontextprotocol/sdk` 1.12.0 through 1.30.1\n- `@modelcontextprotocol/client` 2.0.0 through 2.1.0, only for:\n    - bundled providers without `expectedIssuer`\n    - credentials stored or supplied without `issuer`\n    - direct calls to `fetchToken()`\n    - providers that read storage back through `OAuthTokensSchema` or `OAuthClientInformationSchema`\n\nNot affected:\n\n- MCP servers built with the SDK\n- stdio clients\n\n### Fix\nUpgrade to:\n\n- 1.x: `@modelcontextprotocol/sdk` 1.31.0 or later\n- 2.x: `@modelcontextprotocol/client` 2.2.0 or later, and `@modelcontextprotocol/core` 2.2.0 or later if you import it directly\n\nThe client now records the authorization server as `issuer` on saved credentials and does not send them to a different one. The user signs in again, or the call throws.\n\nIn the following cases, upgrading to the patched version is not enough. You also need to make a change:\n\n- **Bundled providers** (`ClientCredentialsProvider`, `PrivateKeyJwtProvider`, `StaticPrivateKeyJwtProvider`, `CrossAppAccessProvider`): pass `expectedIssuer`, for example `expectedIssuer: 'https://auth.example.com'`. Without it they still use whichever authorization server the MCP server names.\n- **Credentials saved without `issuer`:** tokens and client information your `OAuthClientProvider` persisted (file, keychain, database) before upgrading, including everything 1.x saved before 1.31.0. They still go to whichever authorization server is named at first use. Add `issuer` to them, or clear them so users sign in again.\n- **Your own `OAuthClientProvider`:** save exactly what `saveTokens()` and `saveClientInformation()` are given, including `issuer`. For pre-registered credentials, include `issuer` in what `clientInformation()` returns.\n\nNot covered by this fix:\n\n- a new interactive sign-in, which still goes to the authorization server the MCP server names. Only complete sign-ins for servers you trust.\n- `refreshAuthorization()` and `exchangeAuthorization()` called directly\n- 2.x with `skipIssuerMetadataValidation: true`\n\nIf an affected client may have connected to an untrusted MCP server, rotate its client secret or signing key and revoke its tokens.\n\nIf you cannot upgrade yet, connect OAuth clients only to MCP servers you trust. 2.0.0 and 2.1.0 already accept `expectedIssuer`.","state":0,"publishedAt":"2026-10-06T15:35:44+00:00","modifiedAt":"2026-10-06T15:46:47.1430332+00:00","affected":[{"ecosystem":"npm","name":"@modelcontextprotocol/sdk","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"1.12.0"},{"kind":"fixed","version":"1.31.0"}]}],"versions":[],"rawVersionEvidence":null},{"ecosystem":"npm","name":"@modelcontextprotocol/client","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"2.0.0"},{"kind":"fixed","version":"2.2.0"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V3","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","score":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"HIGH"}],"references":["https://github.com/modelcontextprotocol/typescript-sdk/security/advisories/GHSA-6qxp-vccf-f47h","https://github.com/modelcontextprotocol/typescript-sdk/pull/2887","https://github.com/modelcontextprotocol/typescript-sdk/commit/edd12e282620ebf770d67316f19cf91d4112a1bd","https://github.com/modelcontextprotocol/typescript-sdk","https://github.com/modelcontextprotocol/typescript-sdk/releases/tag/v2.2.0"],"sourceUrl":"https://github.com/advisories/GHSA-6qxp-vccf-f47h","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-6qxp-vccf-f47h","identifiers":["GHSA-6qxp-vccf-f47h","CVE-2026-104850"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. Missing entries do not establish absence of exploitation.","generation":"2026-11-11T13:57:33.6529555+00:00","complete":true,"records":1779,"lastAttemptAt":"2026-11-11T13:57:33.6529555+00:00","lastSuccessAt":"2026-11-11T13:57:33.8241235+00:00","error":null,"lastVerifiedAt":"2026-11-11T13:57:33.8241245+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"cve-program","scope":"Official CVE Program baseline and cumulative hourly delta; all vendors, published and rejected records","generation":"cve-de3b77103708811b6494d2ff7c979037d73ae579742cd1649a5c765137ae5083-50d710c9a9d82d7c4f0dbc882eeaa04edd96b04262f8e1dc90b5d781e709dfb5","complete":true,"records":424128,"lastAttemptAt":"2026-11-11T13:57:32.8474715+00:00","lastSuccessAt":"2026-11-11T13:57:32.6784104+00:00","error":null,"lastVerifiedAt":"2026-11-11T13:57:32.8474715+00:00","snapshotPublishedAt":"2026-11-11T13:27:44+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"euvd","scope":"Rolling EUVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global EUVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-f0a4583a21084daab8e852bf5d038b99","complete":false,"records":13759,"lastAttemptAt":"2026-11-11T14:09:33.1310684+00:00","lastSuccessAt":"2026-11-11T14:09:33.127+00:00","error":null,"lastVerifiedAt":"2026-11-11T14:09:33.127+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13569,"expectedIdentifiers":13813,"failedIdentifiers":0},{"source":"first-epss:nuget","scope":"FIRST EPSS for explicit CVE aliases in the collected public NuGet archive. Not a global EPSS backfill.","generation":"2026-11-11T13:57:33.6529555+00:00","complete":true,"records":1097,"lastAttemptAt":"2026-11-11T13:57:33.6529555+00:00","lastSuccessAt":"2026-11-11T13:57:33.8250558+00:00","error":null,"lastVerifiedAt":"2026-11-11T13:57:33.8250561+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"nvd","scope":"Rolling NVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global NVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-11785b13898646a1917b06b09d2df4a4","complete":true,"records":13753,"lastAttemptAt":"2026-11-11T13:57:34.9144807+00:00","lastSuccessAt":"2026-11-11T13:57:34.909+00:00","error":null,"lastVerifiedAt":"2026-11-11T13:57:34.909+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13813,"expectedIdentifiers":13813,"failedIdentifiers":0},{"source":"osv:Go","scope":"Complete OSV Go ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"go-3562b6c78fd1bd0f0b55daf66a0926ae24f65e462df7f6d928caad458fc696bf","complete":true,"records":9947,"lastAttemptAt":"2026-11-11T13:57:33.3950468+00:00","lastSuccessAt":"2026-11-11T04:27:43.6877707+00:00","error":null,"lastVerifiedAt":"2026-11-11T13:57:33.3950468+00:00","snapshotPublishedAt":"2026-11-11T03:32:46+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:NuGet","scope":"Complete OSV NuGet ecosystem archive, including GitHub Advisory Database records; NuGet version matching only","generation":"nuget-456002455e0ab94bb92c95476d4e6d175c104cd594749982afd96c893728ecbc","complete":true,"records":2010,"lastAttemptAt":"2026-11-11T13:57:32.9057946+00:00","lastSuccessAt":"2026-11-11T02:36:58.1276999+00:00","error":null,"lastVerifiedAt":"2026-11-11T13:57:32.9057946+00:00","snapshotPublishedAt":"2026-11-11T01:17:51+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:crates.io","scope":"Complete OSV crates.io ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"crates.io-baa8362b4daf9e5f39d5563775a55935e7b442c0735d33274a921579ce4a0d66","complete":true,"records":3093,"lastAttemptAt":"2026-11-11T13:57:33.6132068+00:00","lastSuccessAt":"2026-11-11T13:00:02.5446881+00:00","error":null,"lastVerifiedAt":"2026-11-11T13:57:33.6132068+00:00","snapshotPublishedAt":"2026-11-11T12:47:47+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:npm","scope":"Complete OSV npm ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"npm-10cb353ca77c2a8069d6892d1d394d936b12c0add3c8749e2a1a03a1c5d50426","complete":true,"records":231666,"lastAttemptAt":"2026-11-11T13:57:33.0989698+00:00","lastSuccessAt":"2026-11-11T12:59:55.8981437+00:00","error":null,"lastVerifiedAt":"2026-11-11T13:57:33.0989698+00:00","snapshotPublishedAt":"2026-11-11T12:32:53+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null}]}