{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-116684","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-10-26T20:00:59.829Z","datePublished":"2026-10-27T19:12:24.255Z","dateUpdated":"2026-10-27T19:12:24.255Z"},"containers":{"cna":{"title":"Model Context Protocol Python SDK: Server bearer-token authentication accepts tokens issued for a different resource server","problemTypes":[{"descriptions":[{"cweId":"CWE-863","lang":"en","description":"CWE-863: Incorrect Authorization","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":6.8,"baseSeverity":"MEDIUM","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N","version":"3.1"}}],"references":[{"name":"https://github.com/modelcontextprotocol/python-sdk/security/advisories/GHSA-w4fh-qvv9-3v23","tags":["x_refsource_CONFIRM"],"url":"https://github.com/modelcontextprotocol/python-sdk/security/advisories/GHSA-w4fh-qvv9-3v23"},{"name":"https://github.com/modelcontextprotocol/python-sdk/pull/3447","tags":["x_refsource_MISC"],"url":"https://github.com/modelcontextprotocol/python-sdk/pull/3447"},{"name":"https://github.com/modelcontextprotocol/python-sdk/pull/3451","tags":["x_refsource_MISC"],"url":"https://github.com/modelcontextprotocol/python-sdk/pull/3451"},{"name":"https://github.com/modelcontextprotocol/python-sdk/commit/0c9136841ff092987a20700ff9c2c9789bda2f40","tags":["x_refsource_MISC"],"url":"https://github.com/modelcontextprotocol/python-sdk/commit/0c9136841ff092987a20700ff9c2c9789bda2f40"},{"name":"https://github.com/modelcontextprotocol/python-sdk/commit/8c2fa6eabacde869d75568e33b9d466b58c2f512","tags":["x_refsource_MISC"],"url":"https://github.com/modelcontextprotocol/python-sdk/commit/8c2fa6eabacde869d75568e33b9d466b58c2f512"},{"name":"https://github.com/modelcontextprotocol/python-sdk/releases/tag/v1.30.0","tags":["x_refsource_MISC"],"url":"https://github.com/modelcontextprotocol/python-sdk/releases/tag/v1.30.0"},{"name":"https://github.com/modelcontextprotocol/python-sdk/releases/tag/v2.2.0","tags":["x_refsource_MISC"],"url":"https://github.com/modelcontextprotocol/python-sdk/releases/tag/v2.2.0"}],"affected":[{"vendor":"modelcontextprotocol","product":"python-sdk","versions":[{"version":">= 1.10.0, < 1.30.0","status":"affected"},{"version":">= 2.0.0, < 2.2.0","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-10-27T19:12:24.255Z"},"descriptions":[{"lang":"en","value":"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."}],"source":{"advisory":"GHSA-w4fh-qvv9-3v23","discovery":"UNKNOWN"}}}}