CVE-2026-42230 n8n: Open Redirect in MCP OAuth Consent Flow
An attacker can redirect users to malicious sites via the MCP OAuth consent flow if they deny the request, enabling phishing attacks.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-42230?
CVE-2026-42230 is a medium-severity vulnerability in N8n N8n, published on 4 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
n8n is an open source workflow automation platform. Prior to versions 1.123.32, 2.17.4, and 2.18.1, the /mcp-oauth/register endpoint accepted OAuth client registrations without authentication, allowing arbitrary redirect_uri values to be registered. When a user denies the MCP OAuth consent dialog, the handleDeny handler redirects the user to the registered redirect_uri without validation, enabling an open redirect to an attacker-controlled URL. An attacker can craft a phishing link and send it to a victim; if the victim clicks "Deny" on the consent page, they are silently redirected to an external site. This issue has been patched in versions 1.123.32, 2.17.4, and 2.18.1.
Weakness: CWE-601
Which versions are affected by CVE-2026-42230?
6 open source packages ship an affected version, including n8n. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
n8n npm | All versions | 1.123.32 |
n8n npm | All versions | 1.123.32 |
n8n npm | From 2.0.0 | 2.17.4 |
n8n npm | From 2.0.0 | 2.17.4 |
n8n npm | From 2.18.0 | 2.18.1 |
n8n npm | From 2.18.0 | 2.18.1 |
Products include N8n N8n.
How do I fix CVE-2026-42230?
Upgrade n8n to a fixed version for your release line: 1.123.32, 2.17.4 or 2.18.1.
Is CVE-2026-42230 being exploited?
There is no known exploitation of CVE-2026-42230 in the wild and no public exploit code.
Other vulnerabilities in N8n N8n
- CVE-2025-68613 n8n Improper Control of Dynamically-Managed Code Resources
- CVE-2026-21877 n8n is vulnerable to Remote Code Execution via Arbitrary File Write
- CVE-2026-21858 n8n Vulnerable to Unauthenticated File Access via Improper Webhook Request Handling
- CVE-2026-1470 n8n Unsafe Workflow Expression Evaluation Allows Remote Code Execution
- CVE-2025-68668 n8n Vulnerable to Arbitrary Command Execution in Pyodide based Python Code Node
Sources
Also known as GHSA-f6x8-65q6-j9m9.