CVE-2026-4716
Incorrect boundary conditions, uninitialized memory in the JavaScript Engine component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
- Puntuación base: 9.1
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.41%
- Percentil entre todas las CVEs puntuadas: 33
- Fecha de la puntuación: 5/10/2026
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).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1190Exploit Public-Facing Applicationinitial access95 % - Impacto principal
T1005Data from Local Systemcollection85 % - Impacto secundario
T1499.004Application or System Exploitationimpact75 %
AV:N/AC:L/PR:N/UI:N indica explotación remota sin interacción (T1190). Memoria no inicializada en motor JS permite lectura de datos (C:H) y denegación de servicio (A:H).
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
CWE
- CWE-908
- CWE-908
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-4716",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-4716",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-03-25T19:24:14.555574Z"
}
}
],
"cvssMetricV31": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 9.1,
"attackVector": "NETWORK",
"baseSeverity": "CRITICAL",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.2,
"exploitabilityScore": 3.9
},
{
"type": "Secondary",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 9.1,
"attackVector": "NETWORK",
"baseSeverity": "CRITICAL",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.2,
"exploitabilityScore": 3.9
}
]
},
"affected": [
{
"source": "security@mozilla.org",
"affectedData": [
{
"vendor": "Mozilla",
"product": "Firefox",
"versions": [
{
"status": "unaffected",
"version": "140.9",
"versionType": "rpm",
"lessThanOrEqual": "140.*"
},
{
"status": "unaffected",
"version": "149",
"versionType": "rpm",
"lessThanOrEqual": "*"
}
]
},
{
"vendor": "Mozilla",
"product": "Thunderbird",
"versions": [
{
"status": "unaffected",
"version": "140.9",
"versionType": "rpm",
"lessThanOrEqual": "140.*"
},
{
"status": "unaffected",
"version": "149",
"versionType": "rpm",
"lessThanOrEqual": "*"
}
]
}
]
}
],
"published": "2026-03-24T13:16:07.503",
"references": [
{
"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2018592",
"tags": [
"Permissions Required"
],
"source": "security@mozilla.org"
},
{
"url": "https://www.mozilla.org/security/advisories/mfsa2026-20/",
"tags": [
"Vendor Advisory"
],
"source": "security@mozilla.org"
},
{
"url": "https://www.mozilla.org/security/advisories/mfsa2026-22/",
"tags": [
"Vendor Advisory"
],
"source": "security@mozilla.org"
},
{
"url": "https://www.mozilla.org/security/advisories/mfsa2026-23/",
"source": "security@mozilla.org"
},
{
"url": "https://www.mozilla.org/security/advisories/mfsa2026-24/",
"source": "security@mozilla.org"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-908"
}
]
},
{
"type": "Secondary",
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"description": [
{
"lang": "en",
"value": "CWE-908"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Incorrect boundary conditions, uninitialized memory in the JavaScript Engine component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9."
},
{
"lang": "es",
"value": "Condiciones de contorno incorrectas, memoria no inicializada en el componente del motor JavaScript. Esta vulnerabilidad afecta a Firefox < 149, Firefox ESR < 140.9, Thunderbird < 149, y Thunderbird < 140.9."
}
],
"lastModified": "2026-06-17T10:57:06.097",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*",
"vulnerable": true,
"matchCriteriaId": "DA62D95E-CB01-4586-83DB-5094116FC939",
"versionEndExcluding": "140.9.0"
},
{
"criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*",
"vulnerable": true,
"matchCriteriaId": "02F2B82F-E997-4D5F-BBB0-237E4962555B",
"versionEndExcluding": "149.0"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "security@mozilla.org"
}