CVE-2026-4726

Estado: ModificadaAlta (7.5)—

Denial-of-service in the XML component. This vulnerability was fixed in Firefox 149 and Thunderbird 149.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Puntuación base: 7.5

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.52%
Percentil entre todas las CVEs puntuadas: 42
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.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access90 %
Impacto principalT1499 Endpoint Denial of Serviceimpact95 %

Vector CVSS: AV:N/AC:L/PR:N/UI:N con Impact A:H. Red sin privilegios, sin interacción → T1190. CWE-400 (recursos sin límite) causando DoS en componente XML de navegadores públicos → T1499.

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

Filter Network Traffic Vulnerability Scanning Privileged Account Management Network Segmentation Limit Access to Resource Over Network Application Isolation and Sandboxing

Tecnologías afectadas (2)

Mozilla — Firefox Mozilla — Thunderbird

CWE

CWE-400

Referencias

JSON original (NVD)

Mostrar

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  "published": "2026-03-24T13:16:08.473",
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      "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1955311",
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