CVE-2021-23995
Estado: ModificadaAlta (8.8)—
When Responsive Design Mode was enabled, it used references to objects that were previously freed. We presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Puntuación base: 8.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.18%
- Percentil entre todas las CVEs puntuadas: 67
- Fecha de la puntuación: 7/10/2026
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 (3)
CWE
- CWE-672
Referencias
- https://bugzilla.mozilla.org/show_bug.cgi?id=1699835
- https://www.mozilla.org/security/advisories/mfsa2021-14/
- https://www.mozilla.org/security/advisories/mfsa2021-15/
- https://www.mozilla.org/security/advisories/mfsa2021-16/
- https://bugzilla.mozilla.org/show_bug.cgi?id=1699835
- https://www.mozilla.org/security/advisories/mfsa2021-14/
- https://www.mozilla.org/security/advisories/mfsa2021-15/
- https://www.mozilla.org/security/advisories/mfsa2021-16/
JSON original (NVD)
Mostrar
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"authentication": "NONE",
"integrityImpact": "PARTIAL",
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"availabilityImpact": "PARTIAL",
"confidentialityImpact": "PARTIAL"
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"impactScore": 6.4,
"baseSeverity": "MEDIUM",
"obtainAllPrivilege": false,
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"description": [
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"lang": "en",
"value": "CWE-672"
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}
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"descriptions": [
{
"lang": "en",
"value": "When Responsive Design Mode was enabled, it used references to objects that were previously freed. We presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88."
},
{
"lang": "es",
"value": "Cuando se habilitó el Modo de Diseño Responsivo, se usaron referencias a objetos que fueron liberados previamente. Presumimos que con suficiente esfuerzo esto podría haber sido explotado para ejecutar código arbitrario. Esta vulnerabilidad afecta a Firefox ESR versiones anteriores a 78.10, Thunderbird versiones anteriores a 78.10 y Firefox versiones anteriores a 88"
}
],
"lastModified": "2026-06-17T03:39:07.710",
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