CVE-2026-21894: n8n's Missing Stripe-Signature Verification Allows Unauthenticated Forged Webhooks
Impact An authentication bypass in the Stripe Trigger node allows unauthenticated parties to trigger workflows by sending forged Stripe webhook events.
The Stripe Trigger creates and stores a Stripe webhook signing secret when registering the webhook endpoint, but incoming webhook requests were not verified against this secret. As a result, any HTTP client that knows the webhook URL could send a POST request containing a matching event type, causing the workflow to execute as if a legitimate Stripe event had been received.
This issue affects n8n users who have active workflows using the Stripe Trigger node. An attacker could potentially fake payment or subscription events and influence downstream workflow behavior. The practical risk is reduced by the fact that the webhook URL contains a high-entropy UUID; however, authenticated n8n users with access to the workflow can view this webhook ID.
Patches The issue has been fixed in n8n version 2.2.2. Users should upgrade to this version or later to ensure that Stripe webhook signatures are properly verified.
Workarounds There is no complete workaround short of upgrading. As a temporary mitigation, users can deactivate affected workflows or restrict access to workflows containing Stripe Trigger nodes to trusted users only.
Other sources
n8n is an open source workflow automation platform. In versions from 0.150.0 to before 2.2.2, an authentication bypass vulnerability in the Stripe Trigger node allows unauthenticated parties to trigger workflows by sending forged Stripe webhook events. The Stripe Trigger creates and stores a Stripe webhook signing secret when registering the webhook endpoint, but incoming webhook requests were not verified against this secret. As a result, any HTTP client that knows the webhook URL could send a POST request containing a matching event type, causing the workflow to execute as if a legitimate Stripe event had been received. This issue affects n8n users who have active workflows using the Stripe Trigger node. An attacker could potentially fake payment or subscription events and influence downstream workflow behavior. The practical risk is reduced by the fact that the webhook URL contains a high-entropy UUID; however, authenticated n8n users with access to the workflow can view this webhook ID. This issue has been patched in version 2.2.2. A temporary workaround for this issue involves users deactivating affected workflows or restricting access to workflows containing Stripe Trigger nodes to trusted users only.
— MITRE
Affected Software
Remediation
Patch Available
Event History
Frequently Asked Questions
What is the severity of CVE-2026-21894?
CVE-2026-21894 has been classified as a high severity vulnerability due to the potential for unauthorized system access.
How do I fix CVE-2026-21894?
To remediate CVE-2026-21894, upgrade the n8n package to version 2.2.2 or later.
What does CVE-2026-21894 affect?
CVE-2026-21894 affects the Stripe Trigger node in the n8n workflow automation tool.
What kind of exploit is possible with CVE-2026-21894?
CVE-2026-21894 allows unauthenticated users to trigger workflows by forging Stripe webhook events.
Is CVE-2026-21894 present in all versions of n8n?
CVE-2026-21894 is present in n8n versions ranging from 0.150.0 up to, but not including, 2.2.2.