CVE-2026-52870 (GCVE-0-2026-52870)
Vulnerability from cvelistv5
Published
2026-07-15 20:07
Modified
2026-07-16 13:01
Severity ?
7.6 (High) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:L
CWE
Summary
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.
References
Impacted products
Vendor Product Version
modelcontextprotocol python-sdk Version: >= 1.23.0, < 1.27.2
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