CVE-2026-52870highCWE-862

CVE-2026-52870: fallo de gravedad alta en modelcontextprotocol python-sdk

MCP Python SDK: Experimental task handlers allow any client to access and cancel other clients' tasks

Publicada el · Actualizada el

Seguir esta CVE+ Monitorear python-sdk+ Monitorear mcp

Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.

21Vexday Risk Score

Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.

ssvc Trackcvss 7.6epss 0.4%
The MCP Python SDK, called mcp on PyPI, is a Python implementation of the Model Context Protocol (MCP). From 1.23.0 until 1.27.2, default handlers installed by server.experimental.enable_tasks() for tasks/list, tasks/get, tasks/result, and tasks/cancel operate only on task identifiers without recording the session that created each task, allowing any connected client to enumerate, read results from, consume messages for, or cancel other clients' tasks. This issue is fixed in version 1.27.2.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:L
Productos afectados
modelcontextprotocol · python-sdk
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