Vulnerability in N8n
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.0 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.003 (23.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 24th percentile — 23.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- N8n — versions 0, 2.26.2, 2.25.7
Weakness classification (CWE)
References
- github.com/n8n-io/n8n/security/advisories/GHSA-jwm3-qcfw-c5pp (vendor-advisory, Mitigation, Vendor Advisory)
- www.vulncheck.com/advisories/n8n-ast-validator-bypass-in-python-code-node (Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2026-56777?
- CVE-2026-56777 is a medium-severity vulnerability in N8n, classified under Incomplete List of Disallowed Inputs. CVSS score: 5.0/10. Published 2026-06-30.
- How severe is CVE-2026-56777?
- Medium severity. CVSS v3 base score is 5.0 out of 10.