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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-52870 Detail

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/modelcontextprotocol/python-sdk/commit/62137874ff26dd74d2fea80ff528a7fd9ca7a5e7 GitHub, Inc.
https://github.com/modelcontextprotocol/python-sdk/pull/2720 GitHub, Inc.
https://github.com/modelcontextprotocol/python-sdk/releases/tag/v1.27.2 GitHub, Inc.
https://github.com/modelcontextprotocol/python-sdk/security/advisories/GHSA-hvrp-rf83-w775 GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-862 Missing Authorization GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-52870
NVD Published Date:
07/15/2026
NVD Last Modified:
07/15/2026
Source:
GitHub, Inc.