CVEvulnerability
CVE-2026-52870
7.6 HIGH
Official page ↗
- Status
- Analyzed
- Published
- 2026-07-15
- Last modified
- 2026-10-24
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 7.6 HIGH — CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:L
- Weaknesses
- CWE-862
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.
Affected configurations
• lfprojects mcp python sdk (>= 1.23.0 < 1.27.2)
Related
Weakness · CWE (1)
- CWE-862 Missing Authorization weakness
References
- https://github.com/modelcontextprotocol/python-sdk/commit/62137874ff26dd74d2fea80ff528a7fd9ca7a5e7 Patch
- https://github.com/modelcontextprotocol/python-sdk/pull/2720 Issue Tracking, Patch
- https://github.com/modelcontextprotocol/python-sdk/releases/tag/v1.27.2 Release Notes
- https://github.com/modelcontextprotocol/python-sdk/security/advisories/GHSA-hvrp-rf83-w775 Vendor Advisory