High · published June 23, 2026
n8n is an open source workflow automation platform. Prior to 1.123.55, 2.25.7, and 2.26.2, 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. This vulnerability is fixed in 1.123.55, 2.25.7, and 2.26.2.