Which versions of n8n are affected by CVE-2026-42231?

n8n versions prior to 1.123.32, 2.17.4, or 2.18.1 contain a prototype pollution vulnerability in the XML webhook parser that allows authenticated workflow editors to execute arbitrary code on the n8n…. A patch is available.

How to fix or mitigate CVE-2026-42231?

Within 24 hours: Identify all n8n deployments and document current versions. Within 7 days: Upgrade to n8n version 1.123.32 (legacy), 2.17.4 (current LTS), or 2.18.1 (latest stable)-verify your deployment track and select the appropriate fixed version from GitHub advisory GHSA-q5f4-99jv-pgg5. Within 30 days: Audit all workflow editing permissions and restrict to only necessary personnel; review Git node configurations for sensitive operations and confirm no malicious workflows exist in version control history.

n8n CVE-2026-42231

Q: What is the CVSS score of CVE-2026-42231?

CVE-2026-42231 has a CVSS 4.0 base score of 9.4 (Critical). CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. EPSS exploitation probability: 0.5%.

EUVD-2026-27102 CRITICAL

Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution) (CWE-1321)

2026-04-29 https://github.com/n8n-io/n8n

GHSA-q5f4-99jv-pgg5

RCE Prototype Pollution

9.4

CVSS 4.0 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

9.4 CRITICAL

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Lifecycle Timeline

Patch available

May 04, 2026 - 20:01 EUVD

Re-analysis Queued

May 04, 2026 - 19:22 vuln.today

cvss_changed

CVSS changed

May 04, 2026 - 19:22 NVD

10.0 (CRITICAL) 9.4 (CRITICAL)

Source Code Evidence Fetched

Apr 29, 2026 - 22:02 vuln.today

Analysis Generated

Apr 29, 2026 - 22:02 vuln.today

Analysis Generated

Apr 29, 2026 - 21:30 vuln.today

CVE Published

Apr 29, 2026 - 21:25 nvd

CRITICAL 10.0

DescriptionGitHub Advisory

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.

AnalysisAI

Prototype pollution in n8n's XML webhook parser (xml2js library) enables remote code execution when chained with Git node SSH operations. Authenticated users with workflow editing permissions can inject malicious XML payloads to pollute JavaScript object prototypes, then leverage the polluted prototype in Git node operations to execute arbitrary code on the n8n host server. GitHub advisory GHSA-q5f4-99jv-pgg5 confirms patches available in versions 1.123.32, 2.17.4, and 2.18.1. No CISA KEV listing or public POC identified at time of analysis, but the CVSS 10.0 score appears inconsistent with the authenticated (PR:L expected) nature described in the advisory.

Technical ContextAI

This vulnerability exploits a prototype pollution flaw in the xml2js library, a popular Node.js XML-to-JavaScript object parser used by n8n to process XML payloads in webhook requests. Prototype pollution (CWE-1321) occurs when an attacker can inject properties into JavaScript's Object.prototype, affecting all objects in the application. The vulnerability chains this pollution with n8n's Git node, which performs SSH operations. By polluting prototypes with SSH-related properties, an attacker can influence the Git node's command construction or configuration, ultimately achieving arbitrary command execution. The affected package is the n8n npm package across multiple version branches: all versions before 1.123.32, versions 2.17.0-2.17.3, and version 2.18.0. n8n is a workflow automation platform that executes user-defined workflows containing various integration nodes.

RemediationAI

Upgrade n8n to version 1.123.32 (for 1.x deployments), 2.17.4 (for 2.17.x deployments), or 2.18.1 (for 2.18.x deployments) as specified in the vendor advisory at https://github.com/n8n-io/n8n/security/advisories/GHSA-q5f4-99jv-pgg5. For npm-based installations, run npm update n8n and restart the n8n service. Docker users should pull the latest patched image tags. If immediate patching is not feasible, implement the vendor-recommended temporary mitigation by restricting workflow creation and editing permissions exclusively to fully trusted administrators through n8n's role-based access control settings. Note this workaround has trade-offs: it reduces operational flexibility and does not protect against malicious or compromised trusted users. Review existing workflows for suspicious Git node configurations as a precautionary measure. Organizations using n8n Cloud should verify automatic patching status with the vendor. The vendor explicitly states the workaround does not fully remediate risk and should only be used short-term.