Vulnerability 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.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| N8N | N8N | <= 1.123.14 |
Related Weaknesses (CWE)
References
- https://github.com/n8n-io/n8n/commit/b73a4283cb14e0f27ce19692326f362c7bf3da02Patch
- https://research.jfrog.com/vulnerabilities/n8n-python-runner-sandbox-escape-jfsaExploitThird Party Advisory
- https://www.smartkeyss.com/post/cve-2026-0863-python-sandbox-escape-in-n8n-via-eExploitThird Party Advisory
- https://research.jfrog.com/vulnerabilities/n8n-python-runner-sandbox-escape-jfsaExploitThird Party Advisory
FAQ
What is CVE-2026-0863?
CVE-2026-0863 is a vulnerability with a CVSS score of 8.5 (HIGH). 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. T...
How severe is CVE-2026-0863?
CVE-2026-0863 has been rated HIGH with a CVSS base score of 8.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-0863?
Check the references section above for vendor advisories and patch information. Affected products include: N8N N8N.