---
id: CVE-2026-56777
title: n8n - AST Validator Bypass in Python Code Node
summary: >-
  n8n before 2.25.7 and 2.26.x before 2.26.2 contains an abstract syntax tree
  (AST) security validator bypass in the Python Code node. An authenticated user
  with permission to create or modify workflows containing a Python Code node
  can by…
severity: medium
cvss: 5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N'
cvssSource: cna
cwe:
  - CWE-184
vendor: n8n
product: n8n
affected:
  - n8n >= 2.26.0 < 2.26.2
  - n8n < 2.25.7
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-07-01T13:49:24.886291Z'
published: '2026-06-30'
updated: '2026-10-29'
sourceUpdated: '2026-10-29T21:16:00.131Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-56777'
references:
  - url: 'https://github.com/n8n-io/n8n/security/advisories/GHSA-jwm3-qcfw-c5pp'
    label: GitHub Security Advisory (GHSA-jwm3-qcfw-c5pp)
  - url: >-
      https://www.vulncheck.com/advisories/n8n-ast-validator-bypass-in-python-code-node
    label: 'VulnCheck Advisory: n8n - AST Validator Bypass in Python Code Node'
tags:
  - cve.org
epss: 0.00326
epssPercentile: 0.25853
ingestedAt: '2026-11-03T08:39:35.566Z'
---

## Overview

n8n before 2.25.7 and 2.26.x before 2.26.2 contains an abstract syntax tree (AST) security validator bypass in the Python Code node. An authenticated user with permission to create or modify workflows containing a Python Code node can bypass the validator and access the task executor module namespace. The issue only affects self-hosted instances where the Python Task Runner is enabled; where N8N_BLOCK_RUNNER_ENV_ACCESS is configured to allow it, this can disclose environment variables accessible to the task runner process.

## Affected

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

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.