Vulnerability · Published Jan 18, 2026 · Assigned by JFROG
CVE-2026-0863Sandbox escape in n8n Python task runner allows for arbitrary code execution on the underlying host.
High 8.5
In plain English
A high-severity security flaw in n8n. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 9.3% (higher than 95% of all known vulnerabilities).
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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| n8n | 2.4.0 – before 2.4.20 – before 1.123.142.0.0 – before 2.3.5 |
Weakness: CWE-95 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
References
- https://research.jfrog.com/vulnerabilities/n8n-python-runner-sandbox-escape-jfsa-2026-001651077/ third-party-advisory
- https://github.com/n8n-io/n8n/commit/b73a4283cb14e0f27ce19692326f362c7bf3da02 patch
- https://www.smartkeyss.com/post/cve-2026-0863-python-sandbox-escape-in-n8n-via-exception-formatting-and-implicit-code-execution