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CVE-2020-35112

Status: ModifiedHigh (8.8)—

If a user downloaded a file lacking an extension on Windows, and then "Open"-ed it from the downloads panel, if there was an executable file in the downloads directory with the same name but with an executable extension (such as .bat or .exe) that executable would have been launched instead. *Note: This issue only affected Windows operating systems. Other operating systems are unaffected.*. This vulnerability affects Firefox < 84, Thunderbird < 78.6, and Firefox ESR < 78.6.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (3)

Mozilla — FirefoxMozilla — Firefox ESRMozilla — Thunderbird

CWEs

References

Raw JSON (NVD)

Show
{
  "id": "CVE-2020-35112",
  "cveTags": [],
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          "vectorString": "AV:N/AC:M/Au:N/C:P/I:P/A:P",
          "authentication": "NONE",
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        "impactScore": 6.4,
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          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
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          "privilegesRequired": "NONE",
          "confidentialityImpact": "HIGH"
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  ],
  "vulnStatus": "Modified",
  "weaknesses": [
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      "source": "nvd@nist.gov",
      "description": [
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      "value": "If a user downloaded a file lacking an extension on Windows, and then \"Open\"-ed it from the downloads panel, if there was an executable file in the downloads directory with the same name but with an executable extension (such as .bat or .exe) that executable would have been launched instead. *Note: This issue only affected Windows operating systems. Other operating systems are unaffected.*. This vulnerability affects Firefox < 84, Thunderbird < 78.6, and Firefox ESR < 78.6."
    },
    {
      "lang": "es",
      "value": "Si un usuario descargó un archivo que carece de una extensión en Windows y luego \"Open\"-ed desde el panel de descargas, si había un archivo ejecutable en el directorio de descargas con el mismo nombre pero con una extensión ejecutable (como .bat o .exe) ese ejecutable habría sido iniciado en su lugar. *Nota: este problema solo afectó a unos sistemas operativos Windows.&#xa0;Otros sistemas operativos no están afectados.*.&#xa0;Esta vulnerabilidad afecta a Firefox versiones anteriores a 84, Thunderbird versiones anteriores a 78,6 y Firefox ESR versiones anteriores a 78,6"
    }
  ],
  "lastModified": "2026-06-17T03:13:23.980",
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