CVE-2026-42230
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.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected packages
Versions sourced from the GitHub Security Advisory.
| Package | Affected versions | Patched versions |
|---|---|---|
n8nnpm | < 1.123.32 | 1.123.32 |
n8nnpm | >= 2.18.0, < 2.18.1 | 2.18.1 |
n8nnpm | >= 2.0.0, < 2.17.4 | 2.17.4 |
Affected products
2Patches
Vulnerability mechanics
References
3- github.com/advisories/GHSA-f6x8-65q6-j9m9ghsaADVISORY
- github.com/n8n-io/n8n/security/advisories/GHSA-f6x8-65q6-j9m9nvdVendor AdvisoryWEB
- nvd.nist.gov/vuln/detail/CVE-2026-42230ghsaADVISORY
News mentions
1- ⚡ Weekly Recap: Exchange 0-Day, npm Worm, Fake AI Repo, Cisco Exploit and MoreThe Hacker News · May 18, 2026