VULNERABILITY INTELLIGENCE

CVE-2026-52870

CVSS score7.6 HIGH
EPSS probability0.39%
CISA KEVNot currently listed
Published2026-07-15
Last modified2026-10-24
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:L

Description

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.

Weakness classification

  • security-advisories@github.com: CWE-862

Primary references