CVE-2026-110842

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/n8n-io/n8n/security/advisories/GHSA-5jr4-xmvf-frmj
https://www.vulncheck.com/advisories/n8n-before-2.41.4-and-2.42.1-prototype-pollution-via-mcp-workflow-validation-interpreter

Configurations

No configuration.

History

14 Oct 2026, 23:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-14 23:17

Updated : 2026-10-15 14:17

NVD link : CVE-2026-110842

Mitre link : CVE-2026-110842

CVE.ORG link : CVE-2026-110842

JSON object : View

Products Affected

No product.

CWE

CWE-1321

Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

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