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CVE-2020-6814

Status: ModifiedCritical (9.8)—

Mozilla developers reported memory safety bugs present in Firefox and Thunderbird 68.5. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Thunderbird < 68.6, Firefox < 74, Firefox < ESR68.6, and Firefox ESR < 68.6.

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 (4)

Canonical — Ubuntu LinuxMozilla — FirefoxMozilla — Firefox ESRMozilla — Thunderbird

CWEs

References

Raw JSON (NVD)

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{
  "id": "CVE-2020-6814",
  "cveTags": [],
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          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:L/Au:N/C:P/I:P/A:P",
          "authentication": "NONE",
          "integrityImpact": "PARTIAL",
          "accessComplexity": "LOW",
          "availabilityImpact": "PARTIAL",
          "confidentialityImpact": "PARTIAL"
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        "obtainAllPrivilege": false,
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          "baseSeverity": "CRITICAL",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
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          "privilegesRequired": "NONE",
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  "published": "2020-03-25T22:15:13.030",
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      "description": [
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      "lang": "en",
      "value": "Mozilla developers reported memory safety bugs present in Firefox and Thunderbird 68.5. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Thunderbird < 68.6, Firefox < 74, Firefox < ESR68.6, and Firefox ESR < 68.6."
    },
    {
      "lang": "es",
      "value": "Los desarrolladores de Mozilla reportaron bugs de seguridad de la memoria presentes en Firefox y Thunderbird versión 68.5. Algunos de estos bugs mostraron evidencia de corrupción de la memoria y presumimos que con un esfuerzo suficiente algunos de estos podrían haber sido explotados para ejecutar código arbitrario. Esta vulnerabilidad afecta a Thunderbird versiones anteriores a 68.6, Firefox versiones anteriores a 74, Firefox versiones anteriores a ESR68.6 y Firefox ESR versiones anteriores a 68.6."
    }
  ],
  "lastModified": "2026-06-17T03:23:51.350",
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