CVE-2026-2781
Integer overflow in the Libraries component in NSS. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, Thunderbird 140.8, and Firefox ESR 115.35.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 9.8
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.56%
- Percentil entre todas las CVEs puntuadas: 45
- 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
T1059Command and Scripting Interpreterexecution85 % - Impacto secundario
T1068Exploitation for Privilege Escalationprivilege escalation75 %
Integer overflow en NSS de Firefox/Thunderbird (AV:N/PR:N/UI:N) permite ejecución remota de código sin autenticación en aplicaciones de red expuestas. CWE-190 típicamente origina escritura de memoria y ejecución arbitraria.
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 (2)
CWE
- CWE-190
- CWE-190
Referencias
- https://bugzilla.mozilla.org/show_bug.cgi?id=2009552
- https://www.mozilla.org/security/advisories/mfsa2026-13/
- https://www.mozilla.org/security/advisories/mfsa2026-15/
- https://www.mozilla.org/security/advisories/mfsa2026-16/
- https://www.mozilla.org/security/advisories/mfsa2026-17/
- https://www.mozilla.org/security/advisories/mfsa2026-31/
- https://lists.debian.org/debian-lts-announce/2026/03/msg00012.html
JSON original (NVD)
Mostrar
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