n8n before 2.41.4 and 2.42.x before 2.42.1 contains a prototype pollution vulnerability in the MCP workflow-validation tool, whose interpreter evaluates caller-supplied code in the main process, reads inherited properties, and permits assignment onto shared prototypes. An authenticated member holding only a workflow:read grant can replace a built-in method with one returning a truthy value so server-side permission checks accept unheld scopes, enabling takeover of owner accounts not protected by MFA.
History

Thu, 15 Oct 2026 14:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Wed, 14 Oct 2026 23:00:00 +0000

Type Values Removed Values Added
Description n8n before 2.41.4 and 2.42.x before 2.42.1 contains a prototype pollution vulnerability in the MCP workflow-validation tool, whose interpreter evaluates caller-supplied code in the main process, reads inherited properties, and permits assignment onto shared prototypes. An authenticated member holding only a workflow:read grant can replace a built-in method with one returning a truthy value so server-side permission checks accept unheld scopes, enabling takeover of owner accounts not protected by MFA.
Title n8n before 2.41.4 and 2.42.1 Prototype Pollution via MCP Workflow-Validation Interpreter
First Time appeared N8n
N8n n8n
Weaknesses CWE-1321
CPEs cpe:2.3:a:n8n:n8n:*:*:*:*:*:*:*:*
Vendors & Products N8n
N8n n8n
References
Metrics cvssV4_0

{'score': 7.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published: 2026-10-14T22:52:17.341Z

Updated: 2026-10-15T13:44:50.036Z

Reserved: 2026-10-14T22:12:22.055Z

Link: CVE-2026-110842

cve-icon Vulnrichment

Updated: 2026-10-15T13:44:44.143Z

cve-icon NVD

Status : Deferred

Published: 2026-10-14T23:17:24.637

Modified: 2026-10-15T14:17:20.867

Link: CVE-2026-110842

cve-icon Redhat

No data.