CVE-2026-56777
n8n: Python Code Node AST Validator Bypass
描述
## Impact An authenticated user with permission to create or modify workflows containing a Python Code node could bypass the AST security validator and access the task executor module namespace. On self-hosted instances where `N8N_BLOCK_RUNNER_ENV_ACCESS=false` is set, this extended to disclosure of environment variables accessible to the task runner process. This issue only affects instances where the Python Task Runner is enabled and `N8N_BLOCK_RUNNER_ENV_ACCESS=true`. ## Patches The issue has been fixed in n8n versions 2.25.7, and 2.26.2. Users should upgrade to one of these versions or later to remediate the vulnerability. ## Workarounds If upgrading is not immediately possible, administrators should consider the following temporary mitigations: - Limit workflow creation and editing permissions to fully trusted users only. - Disable the Python Code node by adding `n8n-nodes-base.code` to the `NODES_EXCLUDE` environment variable, or disable the Python Task Runner entirely. These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.
如何修補 CVE-2026-56777
要修補 CVE-2026-56777,請將受影響套件升級到下列已修補版本。
- —升級至 2.26.2 或更新版本
CVE-2026-56777 正在被利用嗎?
低 — EPSS 為 0.2%,目前沒有觀察到大規模利用活動。
受影響套件(1)
- >= 2.26.0, < 2.26.2
CVSS 分數
| 來源 | 版本 | 嚴重程度 | 向量 |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N |
| osv | CVSS 3.1 | MEDIUM5.0 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N |