critical CVSS 9.9

CVE-2026-27494·Python vulnerability

n8n is an open source workflow automation platform. Prior to versions 2.10.1, 2.9.3, and 1.123.22, an authenticated user with permission to create or modify workflows could use the Python Code node to escape the sandbox. The sandbox did not sufficiently restrict access to certain built-in Python objects, allowing an attacker to exfiltrate file contents or achieve RCE. On instances using internal Task Runners (default runner mode), this could result in full compromise of the n8n host. On instances using external Task Runners, the attacker might gain access to or impact other task executed on the Task Runner. Task Runners must be enabled using `N8N_RUNNERS_ENABLED=true`. The issue has been fixed in n8n versions 2.10.1, 2.9.3, and 1.123.22. Users should upgrade to this version or later to remediate the vulnerability. If upgrading is not immediately possible, administrators should consider the following temporary mitigations. Limit workflow creation and editing permissions to fully trusted users only., and/or disable the Code node by adding `n8n-nodes-base.code` to the `NODES_EXCLUDE` environment variable. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.

Severity
critical
Software
Python
Fixed in
2.10.1
Published
2026-02-25

Affected versions

From: 2.10.0

Until: 2.10.1

Fixed in: 2.10.1

How to fix this CVE

Upgrade n8n to version 2.10.1, 2.9.3, or 1.123.22 immediately to patch a critical sandbox escape vulnerability in the Python Code node. This vulnerability allows authenticated users to bypass sandbox restrictions and execute arbitrary code or exfiltrate sensitive files. If immediate upgrade is not possible, restrict workflow creation permissions to trusted users only and consider disabling the Code node via the NODES_EXCLUDE environment variable as a temporary measure.

sudo dnf upgrade python3

Defensia detects this vulnerability

How to check if you are affected

  1. Step 1: Check n8n version by running: docker ps | grep n8n or curl http://localhost:5678/api/v1/health (if accessible) and inspect the version field in response
  2. Step 2: Verify if Python Code node is enabled by checking NODES_EXCLUDE environment variable: docker inspect <container_id> | grep NODES_EXCLUDE or inspect your .env file for this setting
  3. Step 3: Search n8n workflow audit logs for Python Code node executions: Check the database or exported workflows for any workflow containing 'n8n-nodes-base.code' node type
  4. Step 4: Confirm patched version after upgrade by executing: n8n --version or inspecting the running container image tag to verify it shows 2.10.1, 2.9.3, 1.123.22 or later

FAQ

What is CVE-2026-27494?

CVE-2026-27494 is a critical sandbox escape vulnerability in n8n's Python Code node that allows authenticated users with workflow modification permissions to bypass Python execution restrictions, potentially leading to remote code execution or sensitive data theft from the host system.

Is CVE-2026-27494 being actively exploited?

No, this vulnerability is not currently listed in the CISA Known Exploited Vulnerabilities catalog and no public exploit code has been released, though the attack vector is straightforward for authenticated users.

What versions of n8n are affected by CVE-2026-27494?

n8n versions prior to 2.10.1, 2.9.3, and 1.123.22 are affected. Specifically, version 2.10.0 and earlier in the 2.10.x branch are vulnerable.

How do I check if my server is vulnerable to CVE-2026-27494?

Run 'n8n --version' or check your running container to identify the version number; if it is below 2.10.1, 2.9.3, or 1.123.22, your instance is vulnerable if the Python Code node is enabled.

Does Defensia detect CVE-2026-27494?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If n8n is installed on a monitored server, CVE-2026-27494 will appear in your dashboard with remediation steps.

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References

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