CVE-2026-21894
MEDIUMn8n's Missing Stripe-Signature Verification Allows Unauthenticated Forged Webhooks
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
n8nnpmDescription
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | n8n | ≥ 0.150.0&&< 2.2.2 | 2.2.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for n8n. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update n8n to 2.2.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-21894 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-21894 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-21894. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-21894 in your dependencies?
O3 detects CVE-2026-21894 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.