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FKIE_CVE-2020-26261

Vulnerability from fkie_nvd - Published: 2020-12-09 17:15 - Updated: 2026-06-17 03:07
Severity
7.9 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
7.9 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
Summary
jupyterhub-systemdspawner enables JupyterHub to spawn single-user notebook servers using systemd. In jupyterhub-systemdspawner before version 0.15 user API tokens issued to single-user servers are specified in the environment of systemd units. These tokens are incorrectly accessible to all users. In particular, the-littlest-jupyterhub is affected, which uses systemdspawner by default. This is patched in jupyterhub-systemdspawner v0.15
References
security-advisories@github.comhttps://github.com/jupyterhub/systemdspawner/blob/master/CHANGELOG.md#v015Release Notes, Third Party Advisory
security-advisories@github.comhttps://github.com/jupyterhub/systemdspawner/commit/a4d08fd2ade1cfd0ef2c29dc221e649345f23580Patch, Third Party Advisory
security-advisories@github.comhttps://github.com/jupyterhub/systemdspawner/security/advisories/GHSA-cg54-gpgr-4rm6Third Party Advisory
security-advisories@github.comhttps://pypi.org/project/jupyterhub-systemdspawner/Product, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/jupyterhub/systemdspawner/blob/master/CHANGELOG.md#v015Release Notes, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/jupyterhub/systemdspawner/commit/a4d08fd2ade1cfd0ef2c29dc221e649345f23580Patch, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/jupyterhub/systemdspawner/security/advisories/GHSA-cg54-gpgr-4rm6Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://pypi.org/project/jupyterhub-systemdspawner/Product, Third Party Advisory
Impacted products
Vendor Product Version
jupyterhub systemdspawner *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "systemdspawner",
          "vendor": "jupyterhub",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 0.15"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:jupyterhub:systemdspawner:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "175655AE-2247-4426-8AE8-0AD5532FBC50",
              "versionEndExcluding": "0.15",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "jupyterhub-systemdspawner enables JupyterHub to spawn single-user notebook servers using systemd. In jupyterhub-systemdspawner before version 0.15 user API tokens issued to single-user servers are specified in the environment of systemd units. These tokens are incorrectly accessible to all users. In particular, the-littlest-jupyterhub is affected, which uses systemdspawner by default. This is patched in jupyterhub-systemdspawner v0.15"
    },
    {
      "lang": "es",
      "value": "jupyterhub-systemdspawner permite que JupyterHub genere servidores de port\u00e1tiles de un solo usuario utilizando systemd.\u0026#xa0;En jupyterhub-systemdspawner, versiones anteriores a 0.15, los tokens de la API de usuario emitidos a servidores de un solo usuario son especificados en el entorno de las unidades systemd.\u0026#xa0;Estos tokens son incorrectamente accesibles para todos los usuarios.\u0026#xa0;En particular, est\u00e1 afectado the-littlest-jupyterhub, que usa systemdspawner por defecto.\u0026#xa0;Esto est\u00e1 parcheado en jupyterhub-systemdspawner versi\u00f3n v0.15"
    }
  ],
  "id": "CVE-2020-26261",
  "lastModified": "2026-06-17T03:07:56.837",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "LOW",
        "cvssData": {
          "accessComplexity": "MEDIUM",
          "accessVector": "LOCAL",
          "authentication": "NONE",
          "availabilityImpact": "NONE",
          "baseScore": 3.3,
          "confidentialityImpact": "PARTIAL",
          "integrityImpact": "PARTIAL",
          "vectorString": "AV:L/AC:M/Au:N/C:P/I:P/A:N",
          "version": "2.0"
        },
        "exploitabilityScore": 3.4,
        "impactScore": 4.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": true
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "NONE",
          "baseScore": 7.9,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "CHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 1.5,
        "impactScore": 5.8,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "NONE",
          "baseScore": 7.9,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "CHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 1.5,
        "impactScore": 5.8,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ]
  },
  "published": "2020-12-09T17:15:30.603",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Release Notes",
        "Third Party Advisory"
      ],
      "url": "https://github.com/jupyterhub/systemdspawner/blob/master/CHANGELOG.md#v015"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/jupyterhub/systemdspawner/commit/a4d08fd2ade1cfd0ef2c29dc221e649345f23580"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://github.com/jupyterhub/systemdspawner/security/advisories/GHSA-cg54-gpgr-4rm6"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Product",
        "Third Party Advisory"
      ],
      "url": "https://pypi.org/project/jupyterhub-systemdspawner/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Release Notes",
        "Third Party Advisory"
      ],
      "url": "https://github.com/jupyterhub/systemdspawner/blob/master/CHANGELOG.md#v015"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Patch",
        "Third Party Advisory"
      ],
      "url": "https://github.com/jupyterhub/systemdspawner/commit/a4d08fd2ade1cfd0ef2c29dc221e649345f23580"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://github.com/jupyterhub/systemdspawner/security/advisories/GHSA-cg54-gpgr-4rm6"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Product",
        "Third Party Advisory"
      ],
      "url": "https://pypi.org/project/jupyterhub-systemdspawner/"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-668"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-668"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    }
  ]
}



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