{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-116685", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-10-26T20:00:59.830Z", "datePublished": "2026-10-27T19:26:46.926Z", "dateUpdated": "2026-10-30T15:03:50.436Z" }, "containers": { "cna": { "title": "Model Context Protocol Python SDK: HTTP client transports followed cross-origin redirects carrying custom headers and bodies", "problemTypes": [ { "descriptions": [ { "cweId": "CWE-200", "lang": "en", "description": "CWE-200: Exposure of Sensitive Information to an Unauthorized Actor", "type": "CWE" } ] } ], "metrics": [ { "cvssV3_1": { "attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.9, "baseSeverity": "MEDIUM", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N", "version": "3.1" } } ], "references": [ { "name": "https://github.com/modelcontextprotocol/python-sdk/security/advisories/GHSA-5h93-6whr-6q8j", "tags": [ "x_refsource_CONFIRM" ], "url": "https://github.com/modelcontextprotocol/python-sdk/security/advisories/GHSA-5h93-6whr-6q8j" }, { "name": "https://github.com/modelcontextprotocol/python-sdk/pull/3397", "tags": [ "x_refsource_MISC" ], "url": "https://github.com/modelcontextprotocol/python-sdk/pull/3397" }, { "name": "https://github.com/modelcontextprotocol/python-sdk/pull/3448", "tags": [ "x_refsource_MISC" ], "url": "https://github.com/modelcontextprotocol/python-sdk/pull/3448" }, { "name": "https://github.com/modelcontextprotocol/python-sdk/commit/2106335745563b2321b8c73fef2c12903d00aa6e", "tags": [ "x_refsource_MISC" ], "url": "https://github.com/modelcontextprotocol/python-sdk/commit/2106335745563b2321b8c73fef2c12903d00aa6e" }, { "name": "https://github.com/modelcontextprotocol/python-sdk/commit/c6762e821c527925f0b617db216d00fbd1d0bf99", "tags": [ "x_refsource_MISC" ], "url": "https://github.com/modelcontextprotocol/python-sdk/commit/c6762e821c527925f0b617db216d00fbd1d0bf99" }, { "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": ">= 1.8.0, < 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": "2026-10-27T19:26:46.926Z" }, "descriptions": [ { "lang": "en", "value": "The Model Context Protocol Python SDK is the official Python SDK for Model Context Protocol servers and clients. From 1.8.0 until 1.30.0 and 2.2.0, streamable_http_client, streamablehttp_client, sse_client, ClientSessionGroup, OAuth, and create_mcp_http_client client paths enable follow_redirects and follow redirects to a different origin, forwarding caller-supplied custom credential headers and, for 307 or 308 responses, the request body. An attacker who can influence a trusted endpoint's redirect destination can receive that material. This issue is fixed in versions 1.30.0 and 2.2.0." } ], "source": { "advisory": "GHSA-5h93-6whr-6q8j", "discovery": "UNKNOWN" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "timestamp": "2026-10-30T15:03:41.785776Z", "id": "CVE-2026-116685", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "role": "CISA Coordinator", "version": "2.0.3" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-30T15:03:50.436Z" } } ] } }