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

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

- **Severity:** High 8.5 (`CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 18 Jan 2026
- **Updated:** 23 Jan 2026
- **Also known as:** GHSA-j6wg-29xj-2fjf

## 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 (Improper Control of Generation of Code), CWE-95 (Improper Neutralization of Directives in Dynamically Evaluated Code)

## Which versions are affected by CVE-2026-0863?

It affects 1 product.


Products: 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.

## Is CVE-2026-0863 being exploited?

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

## Other vulnerabilities in N8n N8n

- [CVE-2025-68613](https://insights.sbomify.com/CVE-2025-68613/): n8n Improper Control of Dynamically-Managed Code Resources (critical 10.0, exploited in the wild)
- [CVE-2026-21877](https://insights.sbomify.com/CVE-2026-21877/): n8n is vulnerable to Remote Code Execution via Arbitrary File Write (critical 10.0)
- [CVE-2026-21858](https://insights.sbomify.com/CVE-2026-21858/): n8n Vulnerable to Unauthenticated File Access via Improper Webhook Request Handling (critical 10.0)
- [CVE-2026-1470](https://insights.sbomify.com/CVE-2026-1470/): n8n Unsafe Workflow Expression Evaluation Allows Remote Code Execution (critical 9.9)
- [CVE-2025-68668](https://insights.sbomify.com/CVE-2025-68668/): n8n Vulnerable to Arbitrary Command Execution in Pyodide based Python Code Node (critical 9.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-0863 and fix it if it is affected.

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

Affected product: N8n N8n. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-0863/ (Markdown: https://insights.sbomify.com/CVE-2026-0863/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-0863
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-0863
- OSV: https://osv.dev/vulnerability/CVE-2026-0863

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-0863/
Summaries are generated and may contain mistakes; the official description above is the record.