CVE-2026-42231: CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') in n8n-io n8n
A critical prototype pollution vulnerability (CWE-1321) exists in the n8n workflow automation platform prior to versions 1.123.32, 2.17.4, and 2.18.1. The flaw arises from the xml2js library used in n8n's webhook handler, allowing an authenticated user with workflow modification permissions to craft an XML payload that pollutes the JavaScript object prototype. By chaining this pollution with the Git node's SSH operations, remote code execution on the n8n host is possible. This vulnerability has been patched in the specified versions.
AI Analysis
Technical Summary
n8n versions before 1.123.32, 2.17.4, and 2.18.1 use a vulnerable xml2js library to parse XML request bodies in their webhook handler. This allows an authenticated user with permissions to create or modify workflows to perform prototype pollution via a crafted XML payload. Exploiting this, combined with the Git node's SSH functionality, can lead to remote code execution on the host running n8n. The issue is addressed by patches released in versions 1.123.32, 2.17.4, and 2.18.1.
Potential Impact
Successful exploitation allows an authenticated user with workflow modification rights to achieve remote code execution on the n8n host system. This can lead to full compromise of the host environment running the vulnerable n8n instance. The CVSS 4.0 score is 9.4 (critical), reflecting the high impact and ease of exploitation given low attack complexity and no user interaction required.
Mitigation Recommendations
This vulnerability is patched in n8n versions 1.123.32, 2.17.4, and 2.18.1. Users should upgrade to these or later versions to remediate the issue. Since this is not a cloud service, remediation depends on applying these official fixes. Patch status is confirmed by the vendor advisory information embedded in the description.
CVE-2026-42231: CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') in n8n-io n8n
Description
A critical prototype pollution vulnerability (CWE-1321) exists in the n8n workflow automation platform prior to versions 1.123.32, 2.17.4, and 2.18.1. The flaw arises from the xml2js library used in n8n's webhook handler, allowing an authenticated user with workflow modification permissions to craft an XML payload that pollutes the JavaScript object prototype. By chaining this pollution with the Git node's SSH operations, remote code execution on the n8n host is possible. This vulnerability has been patched in the specified versions.
CVSS v4.0
Score 9.4critical
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
n8n versions before 1.123.32, 2.17.4, and 2.18.1 use a vulnerable xml2js library to parse XML request bodies in their webhook handler. This allows an authenticated user with permissions to create or modify workflows to perform prototype pollution via a crafted XML payload. Exploiting this, combined with the Git node's SSH functionality, can lead to remote code execution on the host running n8n. The issue is addressed by patches released in versions 1.123.32, 2.17.4, and 2.18.1.
Potential Impact
Successful exploitation allows an authenticated user with workflow modification rights to achieve remote code execution on the n8n host system. This can lead to full compromise of the host environment running the vulnerable n8n instance. The CVSS 4.0 score is 9.4 (critical), reflecting the high impact and ease of exploitation given low attack complexity and no user interaction required.
Mitigation Recommendations
This vulnerability is patched in n8n versions 1.123.32, 2.17.4, and 2.18.1. Users should upgrade to these or later versions to remediate the issue. Since this is not a cloud service, remediation depends on applying these official fixes. Patch status is confirmed by the vendor advisory information embedded in the description.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-25T05:37:12.117Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69f8eaaecbff5d8610415afc
Added to database: 5/4/2026, 6:51:26 PM
Last enriched: 5/12/2026, 6:30:45 AM
Last updated: 6/19/2026, 11:14:20 AM
Views: 78
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