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CVE-2019-9794

Status: ModifiedCritical (9.8)—

A vulnerability was discovered where specific command line arguments are not properly discarded during Firefox invocation as a shell handler for URLs. This could be used to retrieve and execute files whose location is supplied through these command line arguments if Firefox is configured as the default URI handler for a given URI scheme in third party applications and these applications insufficiently sanitize URL data. *Note: This issue only affects Windows operating systems. Other operating systems are unaffected.*. This vulnerability affects Thunderbird < 60.6, Firefox ESR < 60.6, and Firefox < 66.

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 (2)

Mozilla — FirefoxMozilla — Thunderbird

CWEs

References

Raw JSON (NVD)

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  "id": "CVE-2019-9794",
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    },
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      "lang": "es",
      "value": "Fue encontrada una vulnerabilidad donde los argumentos específicos de la línea de comandos no se descartan correctamente durante la invocación de Firefox como un controlador shell para las URL. Esto podría usarse para recuperar y ejecutar archivos cuya ubicación es suministrada por medio de estos argumentos de la línea de comandos si Firefox es configurado como el controlador de URI por defecto para un esquema de URI especifico en aplicaciones de terceros y estas aplicaciones no sanean suficientemente los datos de URL. * Nota: Este problema solo impacta a los sistemas operativos de Windows. Otros sistemas operativos no se ven impactados. *. Esta vulnerabilidad impacta a Thunderbird anterior a la versión 60.6, Firefox ESR anterior a la versión 60.6 y Firefox anterior a la versión 66."
    }
  ],
  "lastModified": "2026-06-17T02:44:21.387",
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