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Luu, T.J.

GHSA-f77h-j2v7-g6mw: n8n Vulnerable to Hijacking of Unauthenticated Chat Execution

mediumvulnerability

security

Source: GitHub Advisory DatabaseApril 29, 2026CVE-2026-42228

Summary

n8n's Chat Trigger feature had a security flaw where the `/chat` WebSocket endpoint (a communication channel) didn't check if users were authorized to access workflow executions. An attacker who could guess a valid execution ID (a unique identifier for a running workflow instance) could connect to an unprotected chat workflow, intercept prompts meant for legitimate users, and inject their own commands to change how the workflow behaves.

Solution / Mitigation

The issue has been fixed in n8n versions 1.123.32, 2.17.4, and 2.18.1. Users should upgrade to one of these versions or later. As a temporary workaround, administrators can enable authentication on all Chat Trigger nodes by setting the Authentication field to `n8n User Auth` rather than `None`, though this does not fully eliminate the risk.