GHSA-22jm-h49p-29qw: High severity npm/@modelcontextprotocol/sdk vulnerability
Summary In affected versions, 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.
Experimental tasks are deprecated. The 2026-07-28 specification replaced them with a redesigned extension. The best course of action is to stop using them.
Am I affected? Only if your HTTP server passes taskStore to McpServer or Server. If grep -ri taskstore --exclude-dir=nodemodules . finds nothing, you are not affected.
Affected versions: @modelcontextprotocol/sdk 1.24.0 through 1.31.0. The 2.x packages are not affected.
Fix Upgrade to @modelcontextprotocol/sdk 1.32.0 or later. Each task is now tied to the session that created it, so a client that starts a new session can no longer reach its earlier tasks.
If you cannot upgrade yet, remove taskStore, or create one InMemoryTaskStore per session.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
npm/@modelcontextprotocol/sdkto a version that resolves this vulnerability.Fixed in 1.32.0 - Upgrade
Upgrade
@modelcontextprotocol/sdkto a version that resolves this vulnerability.Fixed in 1.32.0 - Configuration
If you cannot upgrade, remove taskStore from the HTTP server's McpServer or Server configuration, or create one InMemoryTaskStore per session.
@modelcontextprotocol/sdk experimental tasks taskStore = disabled or one InMemoryTaskStore per session
Event History
Frequently Asked Questions
Which deployments are exposed?
Only HTTP servers that pass taskStore to McpServer or Server are affected. Exposure requires clients to share a single InMemoryTaskStore.
How can I quickly determine whether our code uses the affected feature?
Run grep -ri taskstore --exclude-dir=node_modules . in the project. If it finds nothing, the deployment is not affected.
What can we do if we cannot upgrade immediately?
Remove taskStore, or create a separate InMemoryTaskStore for each session. The recommended longer-term action is to stop using experimental tasks because they are deprecated.
What upgrade resolves the issue?
Upgrade @modelcontextprotocol/sdk to version 1.32.0 or later. Versions 1.24.0 through 1.31.0 are affected, while 2.x packages are not affected.