CVE-2026-42228: n8n: Hijacking of Unauthenticated Chat Execution
Impact The /chat WebSocket endpoint used by the Chat Trigger node's Hosted Chat feature did not verify that an incoming connection was authorized to interact with the target execution. An unauthenticated remote attacker who could identify a valid execution ID for a workflow in a waiting state could attach to that execution, receive the pending prompt intended for the legitimate user, and submit arbitrary input to resume or influence downstream workflow behavior.
Exploitation requires the following conditions: - The instance exposes a public Hosted Chat workflow with authentication set to None. - A target execution is in a waiting state at the time of the attack. - The attacker can obtain or discover the execution ID of that waiting execution.
Patches 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 to remediate the vulnerability.
Workarounds If upgrading is not immediately possible, administrators should consider the following temporary mitigations: - Enable authentication on all Chat Trigger nodes by setting the Authentication field to n8n User Auth rather than None.
These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.
Other sources
n8n is an open source workflow automation platform. Prior to versions 1.123.32, 2.17.4, and 2.18.1, the /chat WebSocket endpoint used by the Chat Trigger node's Hosted Chat feature did not verify that an incoming connection was authorized to interact with the target execution. An unauthenticated remote attacker who could identify a valid execution ID for a workflow in a waiting state could attach to that execution, receive the pending prompt intended for the legitimate user, and submit arbitrary input to resume or influence downstream workflow behavior. This issue has been patched in versions 1.123.32, 2.17.4, and 2.18.1.
— MITRE
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-42228?
CVE-2026-42228 is classified as a critical severity vulnerability due to the ease of exploitation by unauthenticated attackers.
How do I fix CVE-2026-42228?
To fix CVE-2026-42228, update n8n to version 2.17.4 or 2.18.1, or the latest patch available.
What types of systems are affected by CVE-2026-42228?
CVE-2026-42228 affects versions of the n8n package from 2.0.0 to 2.17.4 and specifically version 2.18.0.
Can unauthenticated users exploit CVE-2026-42228?
Yes, an unauthenticated remote attacker can exploit CVE-2026-42228 if they identify a valid execution ID.
What feature in n8n is vulnerable in CVE-2026-42228?
The vulnerability lies in the WebSocket endpoint used by the Chat Trigger node's Hosted Chat feature.