FKIE_CVE-2026-0863

Vulnerability from fkie_nvd - Published: 2026-01-18 16:15 - Updated: 2026-01-20 17:15
Severity ?
8.5 (High) - CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
Summary
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.
References
reefs@jfrog.comhttps://github.com/n8n-io/n8n/commit/b73a4283cb14e0f27ce19692326f362c7bf3da02
reefs@jfrog.comhttps://research.jfrog.com/vulnerabilities/n8n-python-runner-sandbox-escape-jfsa-2026-001651077/
134c704f-9b21-4f2e-91b3-4a467353bcc0https://research.jfrog.com/vulnerabilities/n8n-python-runner-sandbox-escape-jfsa-2026-001651077/
Impacted products
Vendor Product Version
To clipboard 

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Using string formatting and exception handling, an attacker may bypass n8n\u0027s python-task-executor sandbox restrictions and run arbitrary unrestricted Python code in the underlying operating system.\n\nThe 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.\n\nIf the instance is operating under the  \"External\" execution mode (ex. n8n\u0027s official Docker image) - arbitrary code execution occurs inside a Sidecar container and not the main node, which significantly reduces the vulnerability impact."
    }
  ],
  "id": "CVE-2026-0863",
  "lastModified": "2026-01-20T17:15:49.683",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 8.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 6.0,
        "source": "reefs@jfrog.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-01-18T16:15:50.450",
  "references": [
    {
      "source": "reefs@jfrog.com",
      "url": "https://github.com/n8n-io/n8n/commit/b73a4283cb14e0f27ce19692326f362c7bf3da02"
    },
    {
      "source": "reefs@jfrog.com",
      "url": "https://research.jfrog.com/vulnerabilities/n8n-python-runner-sandbox-escape-jfsa-2026-001651077/"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "url": "https://research.jfrog.com/vulnerabilities/n8n-python-runner-sandbox-escape-jfsa-2026-001651077/"
    }
  ],
  "sourceIdentifier": "reefs@jfrog.com",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-95"
        }
      ],
      "source": "reefs@jfrog.com",
      "type": "Secondary"
    }
  ]
}


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