Executive brief
n8n is a workflow automation platform that allows organizations to build and run automated processes. The platform includes approval gates—built-in controls that require manual human approval before executing high-risk actions. This vulnerability allows an anonymous attacker to bypass these approval controls by reusing special tokens that n8n gives to anonymous form submitters, potentially causing unauthorized actions to execute without the intended review.
Technical details
The /chat WebSocket route in n8n resumes paused workflow executions using a resume token without validating that the paused node is actually a chat-capable node type. The vulnerability exists because n8n distributes resume tokens to anonymous form submitters for legitimate use cases, but an attacker can present such a token on the chat route to resume execution at a non-chat node (such as a Send-and-Wait, HITL, or Wait approval gate). This allows bypassing the approval gate without proper authorization. The attack requires network access to the n8n instance and a valid resume token, but no account credentials or user interaction. The fix, available in versions 2.37.7 and 2.38.2, restricts resume operations over the chat route to chat-capable node types only.
Affected products
- n8n n8n < 2.37.7, < 2.38.2
Timeline
- 2026-09-02: disclosed
- 2026-09-02: patched: Fixed in versions 2.37.7 and 2.38.2
- 2026-09-10: advisory