n8n: Same-Origin XSS in Respond to Webhook Node

High7.6CVE-2026-54301 · Published Jun 16, 2026 · updated Jul 20, 2026

## Impact An authenticated user with workflow edit access could configure a `Respond to Webhook` node to serve binary content with an attacker-controlled `Content-Type`. The binary response path bypassed the central `Content-Security-Policy` sandbox header, allowing a public webhook to execute JavaScript in the n8n origin when visited by an authenticated user, with access to that user's session. ## 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 Respond to Webhook node by adding `n8n-nodes-base.respondToWebhook` to the `NODES_EXCLUDE` environment variable. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.