CVE-2026-116684

{"id": "CVE-2026-116684", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 6.8, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "NONE", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 5.2, "exploitabilityScore": 1.6}]}, "affected": [{"source": "security-advisories@github.com", "affectedData": [{"vendor": "modelcontextprotocol", "product": "python-sdk", "versions": [{"status": "affected", "version": ">= 1.10.0, < 1.30.0"}, {"status": "affected", "version": ">= 2.0.0, < 2.2.0"}]}]}], "published": "2026-10-27T20:17:13.307", "references": [{"url": "https://github.com/modelcontextprotocol/python-sdk/commit/0c9136841ff092987a20700ff9c2c9789bda2f40", "source": "security-advisories@github.com"}, {"url": "https://github.com/modelcontextprotocol/python-sdk/commit/8c2fa6eabacde869d75568e33b9d466b58c2f512", "source": "security-advisories@github.com"}, {"url": "https://github.com/modelcontextprotocol/python-sdk/pull/3447", "source": "security-advisories@github.com"}, {"url": "https://github.com/modelcontextprotocol/python-sdk/pull/3451", "source": "security-advisories@github.com"}, {"url": "https://github.com/modelcontextprotocol/python-sdk/releases/tag/v1.30.0", "source": "security-advisories@github.com"}, {"url": "https://github.com/modelcontextprotocol/python-sdk/releases/tag/v2.2.0", "source": "security-advisories@github.com"}, {"url": "https://github.com/modelcontextprotocol/python-sdk/security/advisories/GHSA-w4fh-qvv9-3v23", "source": "security-advisories@github.com"}], "vulnStatus": "Awaiting Analysis", "weaknesses": [{"type": "Primary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-863"}]}], "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."}], "lastModified": "2026-10-28T15:21:31.673", "sourceIdentifier": "security-advisories@github.com"}