CVE-2026-0863 Sandbox escape in n8n Python task runner allows for arbitrary code execution on the underlying host.

High 8.5 Published 18 Jan 2026 Updated 23 Jan 2026

Authenticated users can bypass sandbox restrictions in the Python task runner to execute arbitrary code, potentially taking over the host.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-0863?

CVE-2026-0863 is a high-severity code injection vulnerability in N8n N8n, published on 18 Jan 2026. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

Using string formatting and exception handling, an attacker may bypass n8n's python-task-executor sandbox restrictions and run arbitrary unrestricted Python code in the underlying operating system.

The vulnerability can be exploited via the Code block by an authenticated user with basic permissions and can lead to a full n8n instance takeover on instances operating under "Internal" execution mode.

If the instance is operating under the "External" execution mode (ex. n8n's official Docker image) - arbitrary code execution occurs inside a Sidecar container and not the main node, which significantly reduces the vulnerability impact.

Weakness: CWE-94, CWE-95

Which versions are affected by CVE-2026-0863?

It affects 1 product.

Products include N8n N8n.

How do I fix CVE-2026-0863?

No fix has been published for CVE-2026-0863 yet. Limit exposure of the affected software until one is available.

Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.

Is CVE-2026-0863 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-0863 exists.

All N8n N8n vulnerabilities

Sources

Also known as GHSA-j6wg-29xj-2fjf.