CVE-2026-42235

Published: Mag 04, 2026 Last Modified: Mag 04, 2026
ExploitDB:
Other exploit source:
Google Dorks:
HIGH 8,8
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: active
Confidentiality: N/A
Integrity: N/A
Availability: N/A

Description

AI Translation Available

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.

79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Stable
Abstraction: Base Structure: Simple
Common Consequences
Security Scopes Affected:
Access Control Confidentiality Integrity Availability
Potential Impacts:
Bypass Protection Mechanism Read Application Data Execute Unauthorized Code Or Commands
Applicable Platforms
Technologies: AI/ML, Web Based, Web Server
Likelihood of Exploit: High
View CWE Details
87

Improper Neutralization of Alternate XSS Syntax

Draft
Abstraction: Variant Structure: Simple
Common Consequences
Security Scopes Affected:
Confidentiality Integrity Availability
Potential Impacts:
Read Application Data Execute Unauthorized Code Or Commands
Applicable Platforms
All platforms may be affected
View CWE Details
https://github.com/n8n-io/n8n/security/advisories/GHSA-537j…
https://github.com/n8n-io/n8n/security/advisories/GHSA-537j-gqpc-p7fq