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VULNERABILITIES

CVE-2026-52870 Details

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

CVSS 3.x Severity and Vector Strings:

CNA: [email protected]CVSS-B:7.6 HIGHVector:CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:L

References to Advisories, Solutions, and Tools

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URLSource(s)Tag(s)
https://github.com/modelcontextprotocol/python-sdk/commit/62137874ff26dd74d2fea80ff528a7fd9ca7a5e7 [email protected]Patch
https://github.com/modelcontextprotocol/python-sdk/pull/2720 [email protected]Issue TrackingPatch
https://github.com/modelcontextprotocol/python-sdk/releases/tag/v1.27.2 [email protected]Release Notes
https://github.com/modelcontextprotocol/python-sdk/security/advisories/GHSA-hvrp-rf83-w775 [email protected]Vendor Advisory

Weakness Enumeration

CWE-IDCWE NameSource
CWE-862Missing Authorization[email protected]

Affected Products

ProductVersions
lfprojects mcp python sdk
>= 1.23.0, < 1.27.2

CPE

  • cpe:2.3:a:lfprojects:mcp_python_sdk:*:*:*:*:*:*:*:*

Remediation

  • No remediation found in references.

Change History

3 change records found show changes

QUICK INFO

CVE Dictionary Entry:
CVE-2026-52870
NVD Published Date:
Jul 15, 2026
NVD Last Modified:
Jul 17, 2026
Source:
[email protected]