GHSA-42h7-m79w-wvg5 n8n: Stored XSS in Chat Trigger Node

• npm n8n: < 1.123.55 → fixed in 1.123.55 • npm n8n: >= 2.26.0, < 2.26.2 → fixed in 2.26.2 • npm n8n: >= 2.0.0-rc.0, < 2.25.7 → fixed in 2.25.7

Impact An authenticated user with workflow edit access could inject arbitrary JavaScript into the Chat Trigger's generated page by setting a malicious `webhookId`. When a logged-in user visited the chat URL, the injected code executed in the n8n origin with that user's session privileges. Patches The issue has been fixed in n8n versions 1.123.55, 2.25.7, and 2.26.2. Users should upgrade to one of these versions or later to remediate the vulnerability. Workarounds If upgrading is not immediately possible, administrators should consider the following temporary mitigations: • Limit workflow creation and editing permissions to fully trusted users only. • Disable the Chat Trigger node by adding `@n8n/n8n-nodes-langchain.chatTrigger` to the `NODES_EXCLUDE` environment variable. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.