---
id: GHSA-jwm3-qcfw-c5pp
title: 'n8n: Python Code Node AST Validator Bypass'
summary: 'n8n: Python Code Node AST Validator Bypass'
severity: medium
cvss: 5
cwe:
  - CWE-693
vendor: n8n
product: n8n
ecosystem: npm
affected:
  - 'n8n >= 2.26.0, < 2.26.2'
  - n8n < 2.25.7
patched:
  - n8n 2.26.2
  - n8n 2.25.7
published: '2026-06-16'
updated: '2026-06-16'
source: GHSA
sourceUrl: 'https://github.com/advisories/GHSA-jwm3-qcfw-c5pp'
references:
  - url: 'https://github.com/n8n-io/n8n/security/advisories/GHSA-jwm3-qcfw-c5pp'
  - url: 'https://github.com/advisories/GHSA-jwm3-qcfw-c5pp'
tags:
  - ghsa
  - npm
ingestedAt: '2026-06-29T14:31:47.474Z'
---

## Overview

## Impact
An authenticated user with permission to create or modify workflows containing a Python Code node could bypass the AST security validator and access the task executor module namespace. On self-hosted instances where `N8N_BLOCK_RUNNER_ENV_ACCESS=false` is set, this extended to disclosure of environment variables accessible to the task runner process.

This issue only affects instances where the Python Task Runner is enabled and `N8N_BLOCK_RUNNER_ENV_ACCESS=true`.

## Patches
The issue has been fixed in n8n versions 2.25.7, and 2.26.2. 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.
- Disable the Python Code node by adding `n8n-nodes-base.code` to the `NODES_EXCLUDE` environment variable, or disable the Python Task Runner entirely.

These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.

## Affected packages

- `n8n >= 2.26.0, < 2.26.2`
- `n8n < 2.25.7`

## Remediation

Upgrade to a patched release:

- `n8n 2.26.2`
- `n8n 2.25.7`