CVE-2026-56777

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.

CVSS v3 5.0 MEDIUM

5.0^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.1 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
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

Configurations

No configuration.

History

30 Jun 2026, 23:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-30 23:17

Updated : 2026-06-30 23:17

NVD link : CVE-2026-56777

Mitre link : CVE-2026-56777

CVE.ORG link : CVE-2026-56777

JSON object : View

Products Affected

No product.

CWE

CWE-184

Incomplete List of Disallowed Inputs

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