# CVE-2026-56777: n8n - AST Validator Bypass in Python Code Node

> CVE-2026-56777: n8n - AST Validator Bypass in Python Code Node. CVSS 5.0 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-56777
Last updated: 2026-10-25T17:10:00Z

- Published: 2026-06-30 22:08 UTC · Updated: 2026-10-25 17:10 UTC · Assigner: VulnCheck
- CVSS: 5.0 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N
- EPSS: 0.33%, 25th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-184

## Description

n8n before 2.25.7 and 2.26.x before 2.26.2 contains an abstract syntax tree (AST) security validator bypass in the Python Code node. An authenticated user with permission to create or modify workflows containing a Python Code node can bypass the validator and access the task executor module namespace. The issue only affects self-hosted instances where the Python Task Runner is enabled; where N8N\_BLOCK\_RUNNER\_ENV\_ACCESS is configured to allow it, this can disclose environment variables accessible to the task runner process.

## Affected vendors and products

- n8n: n8n

## Tracked companies

- [n8n](https://rewindex.com/company/n8n.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-56777)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-56777)
- [https://github.com/n8n-io/n8n/security/advisories/GHSA-jwm3-qcfw-c5pp](https://github.com/n8n-io/n8n/security/advisories/GHSA-jwm3-qcfw-c5pp)
- [https://www.vulncheck.com/advisories/n8n-ast-validator-bypass-in-python-code-node](https://www.vulncheck.com/advisories/n8n-ast-validator-bypass-in-python-code-node)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-56777 · Markdown: https://rewindex.com/cve/CVE-2026-56777.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-56777 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:11:42.799Z