CVE-2026-6658

{
  "id": "CVE-2026-6658",
  "sourceIdentifier": "[email protected]",
  "published": "2026-06-26T10:16:22.810",
  "lastModified": "2026-10-25T22:10:00.150",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A vulnerability in jupyter/nbconvert versions <= 7.17.0 allows for Cross-site Scripting (XSS) via unsanitized `text/vnd.mermaid` output in HTML exports. The `data_mermaid` block in `share/templates/lab/base.html.j2` renders `text/vnd.mermaid` cell output directly into HTML without escaping, enabling attackers to inject arbitrary HTML/JavaScript by breaking out of the `<pre>` tag. This vulnerability impacts any server using nbconvert to render notebooks as HTML, allowing attackers to execute arbitrary JavaScript in the context of users viewing the HTML export."
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad en las versiones menor o igual que 7.17.0 de jupyter/nbconvert permite cross-site scripting (XSS) a través de la salida ’text/vnd.mermaid’ sin sanitizar en las exportaciones HTML. El bloque ’data_mermaid’ en ’share/templates/lab/base.html.j2’ renderiza la salida de celda ’text/vnd.mermaid’ directamente en HTML sin escapar, permitiendo a los atacantes inyectar HTML/JavaScript arbitrario al salir de la etiqueta ’[pre]’. Esta vulnerabilidad afecta a cualquier servidor que utilice nbconvert para renderizar cuadernos como HTML, permitiendo a los atacantes ejecutar JavaScript arbitrario en el contexto de los usuarios que visualizan la exportación HTML."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "jupyter",
          "product": "jupyter/jupyter",
          "versions": [
            {
              "version": "unspecified",
              "lessThanOrEqual": "latest",
              "versionType": "custom",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV30": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.0",
          "vectorString": "CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N",
          "baseScore": 5.4,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "REQUIRED",
          "scope": "CHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 2.3,
        "impactScore": 2.7
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-06-26T10:19:03.505659Z",
          "id": "CVE-2026-6658",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://huntr.com/bounties/47570290-3b26-4477-8cfa-fdef7db5aefe",
      "source": "[email protected]"
    },
    {
      "url": "https://huntr.com/bounties/47570290-3b26-4477-8cfa-fdef7db5aefe",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ]
}