CVE-2026-116686
CVE-2026-116686 · Model Context Protocol Python SDK: Client fetched server-chosen $ref URLs while validating tool results against output schemas
Cette page présente des faits issus de sources publiques. Consultez l’avis original avant toute mise à jour.
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, ClientSession, ClientSessionGroup, and Client tool calls validate server-declared outputSchema documents with jsonschema's default resolver, causing an unresolved $ref value to fetch an HTTP, HTTPS, or file URL from the client's network and filesystem context. A server can trigger blind requests or local-file reads and can stall every session in the process because resolution runs synchronously on the event loop without a timeout. This issue is fixed in versions 1.30.0 and 2.2.0.
CVSS 6.5 · Moyenne · EPSS 0,3% · Correctif disponible
- Publication
- Mise à jour
Pile logicielle: python
Produits et versions concernés
python-sdk
- Versions du logiciel
- >= 1.10.0, < 1.30.0: Concernée
- >= 2.0.0, < 2.2.0: Concernée
Aucun correctif publié
mcp PyPI
- Versions du logiciel
- 2.0.0
- 2.0.1
- 2.1.0
- 2.1.1
- Plages de versions concernées
- ECOSYSTEM: ≥ 2.0.0, < 2.2.0
Mettez à jour vers 2.2.0
mcp PyPI
- Versions du logiciel
- 1.10.0
- 1.10.1
- 1.11.0
- 1.12.0
- 1.12.1
- 1.12.2
- 1.12.3
- 1.12.4
- 1.13.0
- 1.13.1
- 1.14.0
- 1.14.1
- 1.15.0
- 1.16.0
- 1.17.0
- 1.18.0
- 1.19.0
- 1.20.0
- 1.21.0
- 1.21.1
- 1.21.2
- 1.22.0
- 1.23.0
- 1.23.1
- 1.23.2
- 1.23.3
- 1.24.0
- 1.25.0
- 1.26.0
- 1.27.0
- 1.27.1
- 1.27.2
- 1.28.0
- 1.28.1
- 1.29.0
- 1.29.1
- Plages de versions concernées
- ECOSYSTEM: ≥ 1.10.0, < 1.30.0
Mettez à jour vers 1.30.0
Sources originales
- https://github.com/modelcontextprotocol/python-sdk/security/advisories/GHSA-rwrf-2pqf-9j8j
- https://github.com/modelcontextprotocol/python-sdk/pull/3394
- https://github.com/modelcontextprotocol/python-sdk/pull/3396
- https://github.com/modelcontextprotocol/python-sdk/commit/5ebdfed4060d8e5b11b8e2348f86bad4d1fb8836
- https://github.com/modelcontextprotocol/python-sdk/commit/6705402e246dc4eb1fcdf4d9902b78d3c9c36e1b
- https://github.com/modelcontextprotocol/python-sdk/releases/tag/v1.30.0
- https://github.com/modelcontextprotocol/python-sdk/releases/tag/v2.2.0
- https://nvd.nist.gov/vuln/detail/CVE-2026-116686