What is CVE-2026-111767?

CVE-2026-111767 is a high-severity vulnerability in Modelcontextprotocol Typescript-Sdk, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 8.6/10. Published 2026-10-20.

How severe is CVE-2026-111767?

High severity. CVSS v3 base score is 8.6 out of 10.

Auth bypass in Modelcontextprotocol Typescript-Sdk

CVE-2026-111767

MCP TypeScript SDK is the official TypeScript SDK for Model Context Protocol servers and clients. From version 1.24.0 to before version 1.32.0, the experimental tasks feature (taskStore) did not check which session created a task. Clients sharing one InMemoryTaskStore could list, read and cancel each other's tasks. This issue has been patched in version 1.32.0.

Vulnerability class: IDOR (Insecure Direct Object Reference)

Published 2026-10-20 · last modified 2026-10-20.

CVSS v3 metric

CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Modelcontextprotocol Typescript-Sdk — versions >= 1.24.0, < 1.32.0

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-111767?: CVE-2026-111767 is a high-severity vulnerability in Modelcontextprotocol Typescript-Sdk, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 8.6/10. Published 2026-10-20.
How severe is CVE-2026-111767?: High severity. CVSS v3 base score is 8.6 out of 10.