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CVE-2020-11934

Estado: ModificadaMedia (5.9)—

It was discovered that snapctl user-open allowed altering the $XDG_DATA_DIRS environment variable when calling the system xdg-open. OpenURL() in usersession/userd/launcher.go would alter $XDG_DATA_DIRS to append a path to a directory controlled by the calling snap. A malicious snap could exploit this to bypass intended access restrictions to control how the host system xdg-open script opens the URL and, for example, execute a script shipped with the snap without confinement. This issue did not affect Ubuntu Core systems. Fixed in snapd versions 2.45.1ubuntu0.2, 2.45.1+18.04.2 and 2.45.1+20.04.2.

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

Tecnologías afectadas (1)

Canonical — Ubuntu Linux

CWE

Referencias

JSON original (NVD)

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{
  "id": "CVE-2020-11934",
  "cveTags": [],
  "metrics": {
    "cvssMetricV2": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "version": "2.0",
          "baseScore": 1.9,
          "accessVector": "LOCAL",
          "vectorString": "AV:L/AC:M/Au:N/C:N/I:P/A:N",
          "authentication": "NONE",
          "integrityImpact": "PARTIAL",
          "accessComplexity": "MEDIUM",
          "availabilityImpact": "NONE",
          "confidentialityImpact": "NONE"
        },
        "acInsufInfo": false,
        "impactScore": 2.9,
        "baseSeverity": "LOW",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 3.4,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": true
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "security@ubuntu.com",
        "cvssData": {
          "scope": "CHANGED",
          "version": "3.1",
          "baseScore": 5.9,
          "attackVector": "LOCAL",
          "baseSeverity": "MEDIUM",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:N/I:H/A:N",
          "integrityImpact": "HIGH",
          "userInteraction": "REQUIRED",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "NONE"
        },
        "impactScore": 4,
        "exploitabilityScore": 1.5
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      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
          "scope": "CHANGED",
          "version": "3.1",
          "baseScore": 5.9,
          "attackVector": "LOCAL",
          "baseSeverity": "MEDIUM",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:N/I:H/A:N",
          "integrityImpact": "HIGH",
          "userInteraction": "REQUIRED",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "NONE"
        },
        "impactScore": 4,
        "exploitabilityScore": 1.5
      }
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  },
  "affected": [
    {
      "source": "security@ubuntu.com",
      "affectedData": [
        {
          "vendor": "Canonical",
          "product": "snapd",
          "versions": [
            {
              "status": "affected",
              "changes": [
                {
                  "at": "2.45.1+18.04.2",
                  "status": "unaffected"
                },
                {
                  "at": "2.45.1+20.04.2",
                  "status": "unaffected"
                }
              ],
              "version": "2.45.1",
              "lessThan": "2.45.1ubuntu0.2",
              "versionType": "custom"
            }
          ]
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      ]
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  ],
  "published": "2020-07-29T17:15:12.967",
  "references": [
    {
      "url": "https://launchpad.net/bugs/1880085",
      "tags": [
        "Third Party Advisory"
      ],
      "source": "security@ubuntu.com"
    },
    {
      "url": "https://ubuntu.com/USN-4424-1",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "security@ubuntu.com"
    },
    {
      "url": "https://launchpad.net/bugs/1880085",
      "tags": [
        "Third Party Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    },
    {
      "url": "https://ubuntu.com/USN-4424-1",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "af854a3a-2127-422b-91ae-364da2661108"
    }
  ],
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "type": "Primary",
      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-668"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "It was discovered that snapctl user-open allowed altering the $XDG_DATA_DIRS environment variable when calling the system xdg-open. OpenURL() in usersession/userd/launcher.go would alter $XDG_DATA_DIRS to append a path to a directory controlled by the calling snap. A malicious snap could exploit this to bypass intended access restrictions to control how the host system xdg-open script opens the URL and, for example, execute a script shipped with the snap without confinement. This issue did not affect Ubuntu Core systems. Fixed in snapd versions 2.45.1ubuntu0.2, 2.45.1+18.04.2 and 2.45.1+20.04.2."
    },
    {
      "lang": "es",
      "value": "Se detectó que snapctl user-open permitía alterar la variable de entorno $XDG_DATA_DIRS cuando se llama al sistema xdg-open. La función OpenURL() en el archivo usersession/userd/launcher.go alteraría $XDG_DATA_DIRS para agregar una ruta a un directorio controlado por el complemento de llamada. Un complemento malicioso podría explotar esto para omitir las restricciones de acceso previstas para controlar cómo el script xdg-open del sistema host abre la URL y, por ejemplo, ejecuta un script enviado con el complemento sin confinamiento. Este problema no afectó a los sistemas Ubuntu Core. Corregido en las versiones snapd 2.45.1ubuntu0.2, 2.45.1+18.04.2 y 2.45.1+20.04.2"
    }
  ],
  "lastModified": "2026-06-17T02:51:05.153",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
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              "criteria": "cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*",
              "vulnerable": true,
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          "operator": "OR"
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  "sourceIdentifier": "security@ubuntu.com"
}