CVE-2026-42231

CRITICAL

n8n has Prototype Pollution in XML Webhook Body Parser that Leads to RCE

Published April 29, 2026Updated May 8, 2026Source: osv

Summary

## Impact A flaw in the `xml2js` library used to parse XML request bodies in n8n's webhook handler allowed prototype pollution via a crafted XML payload. An authenticated user with permission to create or modify workflows could exploit this to pollute the JavaScript object prototype and, by chaining the pollution with the Git node's SSH operations, achieve remote code execution on the n8n host. ## Patches The issue has been fixed in n8n versions 1.123.32, 2.17.4, and 2.18.1. Users should upgrade to one of these versions or later to remediate the vulnerability. ## Workarounds If upgrading is not immediately possible, administrators should consider the following temporary mitigations: - Limit workflow creation and editing permissions to fully trusted users only. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures. --- n8n has adopted CVSS 4.0 as primary score for all security advisories. CVSS 3.1 vector strings are provided for backwards compatibility. CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Remediation

Upgrade to the fixed version using your package manager.

npm

Update n8n to 2.18.1 or later

npm install n8n@2.18.1

npm

Update n8n to 1.123.32 or later

npm install n8n@1.123.32

npm

Update n8n to 2.17.4 or later

npm install n8n@2.17.4

After upgrading, run your dependency scanner again to confirm the vulnerability is resolved.

Affected Packages (3)

Package	Ecosystem	Affected	Fixed In
n8n	npm	All versions	2.18.1
n8n	npm	All versions	1.123.32
n8n	npm	All versions	2.17.4

Vulnerability Classification

Common Weakness Enumeration (CWE) identifiers for this vulnerability type.

CWE-1321
Prototype PollutionMITRE

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 10.0 score means for each attack dimension.

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

References

Frequently Asked Questions

What is CVE-2026-42231?: n8n has Prototype Pollution in XML Webhook Body Parser that Leads to RCE This vulnerability has been assigned a severity rating of CRITICAL (CVSS score: 10.0/10).
How do I check if my project is affected by CVE-2026-42231?: CVE-2026-42231 affects n8n. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2026-42231 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score

10.0

Exploitation is straightforward and causes maximum impact. Patch immediately.

Also Known As

GHSA-q5f4-99jv-pgg5

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