n8n-io n8n up to 2.41.3/2.42.0 MCP workflow-validation tool prototype pollution

Summaryinfo

A vulnerability was found in n8n-io n8n up to 2.41.3/2.42.0 and classified as critical. Affected by this issue is some unknown functionality of the component MCP workflow-validation tool. Such manipulation leads to prototype pollution. This vulnerability is referenced as CVE-2026-110842. It is possible to launch the attack remotely. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in n8n-io n8n up to 2.41.3/2.42.0. Affected by this issue is an unknown code of the component MCP workflow-validation tool. The manipulation with an unknown input leads to a prototype pollution vulnerability. Using CWE to declare the problem leads to CWE-1321. The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype. Impacted is confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-110842 since 10/15/2026. The exploitation is known to be easy. The attack may be launched remotely. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1059 by the MITRE ATT&CK project.

Upgrading to version 2.41.4 or 2.42.1 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

• n8n-io

Name

• n8n

Version

• 2.0
• 2.1
• 2.2
• 2.3
• 2.4
• 2.5
• 2.6
• 2.7
• 2.8
• 2.9
• 2.10
• 2.11
• 2.12
• 2.13
• 2.14
• 2.15
• 2.16
• 2.17
• 2.18
• 2.19
• 2.20
• 2.21
• 2.22
• 2.23
• 2.24
• 2.25
• 2.26
• 2.27
• 2.28
• 2.29
• 2.30
• 2.31
• 2.32
• 2.33
• 2.34
• 2.35
• 2.36
• 2.37
• 2.38
• 2.39
• 2.40
• 2.41
• 2.41.0
• 2.41.1
• 2.41.2
• 2.41.3
• 2.42.0

Website

• Product: https://github.com/n8n-io/n8n/

CPE 2.3info

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CPE 2.2info

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Entryinfo

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