GHSA-35jj-42hp-8gmq: n8n: Anonymous Approval-Gate Bypass via Reused resumeToken over the Chat WebSocket
Summary
A security flaw in n8n (a workflow automation tool) allowed anyone without an account to bypass approval gates (checkpoints that require human approval before executing important actions) by reusing a special token called a resumeToken on the chat route. The issue occurred because the system didn't verify that the token was being used for the correct type of node, allowing unauthorized users to complete workflows that should have required approval.
Solution / Mitigation
The issue has been fixed in n8n versions 2.37.7 and 2.38.2. Users should upgrade to one of these versions or later to remediate the vulnerability. If upgrading is not immediately possible, administrators should: (1) restrict n8n instance access to fully trusted users only, (2) avoid workflows that combine a Form Trigger with non-chat approval gates (Send-and-Wait, Telegram/Slack/Gmail HITL, or plain Wait nodes) on publicly accessible instances, and (3) audit recent executions of such workflows for unexpected completion without a corresponding approval callback. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.
Vulnerability Details
EPSS: 0.4%
Yes
September 10, 2026
Classification
Taxonomy References
Affected Vendors
Affected Packages
Related Issues
Original source: https://github.com/advisories/GHSA-35jj-42hp-8gmq
First tracked: September 10, 2026 at 08:01 PM
Classified by LLM (prompt v3) · confidence: 85%