GHSA-q7jr-6fm4-vvhg: 
JavaScript vulnerability analysis and mitigation

Impact

These issues affect n8n-mcp in HTTP mode. They require a caller who holds the server's AUTH_TOKEN.

• Multi-tenant mode (ENABLE_MULTI_TENANT=true, instance session strategy): a caller could end other clients' sessions for an instance ID without that instance's credentials.
• Session IDs: a session's ID could be chosen by the client. A caller who knew another client's live session ID could replace that session.
• n8n_test_workflow: some trigger paths could reach other paths on the configured n8n instance. Configured Cloudflare Access service-token headers were sent with those requests. n8n's own authentication still applied.

Affected versions

n8n-mcp 2.99.1 and earlier.

Patched versions

2.99.2.

Workarounds

• Give AUTH_TOKEN only to trusted clients, and restrict who can reach the HTTP endpoint.
• Use stdio mode, which has no HTTP sessions.

Credit

Reported by @3099404236.