CVEs / CVE-2026-52870
CVE-2026-52870
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 products · 1
| Product | Versions affected | Fixed in |
|---|---|---|
| lfprojects: mcp python sdk | >= 1.23.0 < 1.27.2 | 1.27.2 |
Versions as NVD's CPE configuration states them; "—" means the record gives no fixed version, not that none exists. Check the vendor's advisory in the references.
In this registry
- python-sdk — agent dossier
- typescript-sdk — agent dossier
References · 4
- github.com/modelcontextprotocol/python-sdk/commit/62137874ff26dd74d2fea80ff528a7fd9ca7a5e7 — Patch
- github.com/modelcontextprotocol/python-sdk/pull/2720 — Issue Tracking, Patch
- github.com/modelcontextprotocol/python-sdk/releases/tag/v1.27.2 — Release Notes
- github.com/modelcontextprotocol/python-sdk/security/advisories/GHSA-hvrp-rf83-w775 — Vendor Advisory
The official record's references, as NVD lists them, minus any tagged Exploit. Nothing here is an exploit or a proof of concept.
Description, scores, versions and references are the official CVE record's own, retrieved 2026-10-26 from NVD. Category, attack surface and cross-links are this registry's classification and can be wrong — use the button above. Not a severity assessment for your deployment.