high CVSS 8.8

CVE-2026-42234·Python vulnerability

n8n is an open source workflow automation platform. Prior to versions 1.123.32, 2.17.4, and 2.18.1, an authenticated user with permission to create or modify workflows containing a Python Code Node could escape the sandbox and achieve arbitrary code execution on the task runner container. This issue only affects instances where the Python Task Runner is enabled. This issue has been patched in versions 1.123.32, 2.17.4, and 2.18.1.

Severity
high
Software
Python
Fixed in
2.17.4
Published
2026-05-04

Affected versions

From: 2.17.0

Until: 2.17.4

Fixed in: 2.17.4

How to fix this CVE

Upgrade n8n to version 2.17.4 or later to patch the Python Code Node sandbox escape vulnerability. If you are running n8n versions 2.17.0 through 2.17.3 with the Python Task Runner enabled, authenticated users can potentially execute arbitrary code on the task runner container by crafting malicious Python workflows. Verify your n8n installation version and apply the update immediately.

sudo dnf update python3

Defensia detects this vulnerability

How to check if you are affected

  1. Check n8n version: curl -s http://localhost:5678/api/v1/health | grep -i version or inspect the n8n container/process
  2. Verify if Python Task Runner is enabled: Check n8n_PYTHON_TASK_RUNNER environment variable or configuration file for true/enabled status
  3. Search container/application logs for unusual Python subprocess execution: grep -i 'python\|subprocess\|exec' /var/log/n8n/*.log or container logs
  4. Confirm patch by verifying n8n version is 2.17.4, 2.18.1, or 1.123.32+: Compare installed version against fixed versions in release notes

FAQ

What is CVE-2026-42234?

This vulnerability allows authenticated n8n users with workflow modification permissions to escape the Python Code Node sandbox and execute arbitrary code directly on the task runner container when the Python Task Runner feature is enabled.

Is CVE-2026-42234 being actively exploited?

No, this vulnerability is not listed on the CISA Known Exploited Vulnerabilities (KEV) catalog and no public exploits are currently available.

What versions of n8n are affected by CVE-2026-42234?

Versions 2.17.0 through 2.17.3 are vulnerable. Versions 1.x prior to 1.123.32 and 2.x prior to 2.17.4 or 2.18.1 may also be affected depending on your specific release track.

How do I check if my server is vulnerable to CVE-2026-42234?

Run 'curl -s http://localhost:5678/api/v1/health 2>/dev/null | grep version' to check n8n version, then verify Python Task Runner is enabled by checking environment variables or configuration files.

Does Defensia detect CVE-2026-42234?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If n8n is installed on a monitored server, CVE-2026-42234 will appear in your dashboard with remediation steps.

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References

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