MCP TypeScript SDK: experimental tasks not tied to the session that created them

What's on the official record

The OSV advisory GHSA-22jm-h49p-29qw, published 20 October 2026, reports a HIGH-severity vulnerability in the npm package @modelcontextprotocol/sdk (MCP TypeScript SDK, mcp layer), aliased CVE-2026-111767 and classified under CWE-639 and CWE-862. The advisory states that in affected versions the experimental tasks feature (taskStore) did not check which session created a task, so clients sharing one InMemoryTaskStore could list, read and cancel each other's tasks. The advisory names fixed version 1.32.0. Experimental tasks are deprecated. FIRST's EPSS estimate is 0.003 (p27, 2026-10-23).

Assessment

For a platform-ai-stack-owner, the record lets this reader check whether any MCP TypeScript SDK deployment runs the experimental tasks feature with a shared InMemoryTaskStore, and decide whether to pin to 1.32.0 or disable the deprecated feature.

For a deal-team, the record lets this reader check whether a target's MCP-based agent stack depends on an affected @modelcontextprotocol/sdk version below 1.32.0, and decide whether that dependency changes diligence scope or pricing.

What would change this call

A fixed version other than 1.32.0, a statement that the experimental tasks feature is not deprecated, or evidence that a given deployment does not share one InMemoryTaskStore across clients would change this call.

What to check next

Confidence

This note is drawn from the single OSV advisory row (GHSA-22jm-h49p-29qw). The advisory id, package and ecosystem, severity, fixed version, CWE classifications, and publication date are taken directly from that row.

Sources

[1] OSV advisory GHSA-22jm-h49p-29qw — https://github.com/advisories/GHSA-22jm-h49p-29qw