9.6

CVE-2026-42235

n8n: XSS via MCP OAuth client

n8n is an open source workflow automation platform. Prior to versions 1.123.32, 2.17.4, and 2.18.1, an unauthenticated attacker could register a malicious MCP OAuth client with a crafted client_name. If a victim user authorized the OAuth consent dialog and a second user subsequently revoked that access, a toast notification would render the injected script. Clicking the link would execute arbitrary JavaScript in the victim's authenticated n8n browser session, enabling credential and session token theft, workflow manipulation, or privilege escalation. This issue has been patched in versions 1.123.32, 2.17.4, and 2.18.1.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
N8n ≫ N8n SwEditionenterprise SwPlatformnode.js Version < 1.123.32
N8n ≫ N8n SwEditionenterprise SwPlatformnode.js Version >= 2.17.0 < 2.17.4
N8n ≫ N8n Version2.18.0 SwEditionenterprise SwPlatformnode.js
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.33% 0.248
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
nvd@nist.gov 9.6 2.8 6
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
security-advisories@github.com 8.8 0 0
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:L/SC:H/SI:H/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

CWE-87 Improper Neutralization of Alternate XSS Syntax

The product does not neutralize or incorrectly neutralizes user-controlled input for alternate script syntax.

https://github.com/n8n-io/n8n/security/advisories/GHSA-537j-gqpc-p7fq
Vendor Advisory