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CVE-2025-5270

Estado: ModificadaAlta (7.5)—

In certain cases, SNI could have been sent unencrypted even when encrypted DNS was enabled. This vulnerability was fixed in Firefox 139 and Thunderbird 139.

CVSS

Probabilidad de explotación (EPSS)

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.

Vulnerabilidad de red en Firefox (AV:N, PR:N, UI:N) que expone información sensible (SNI sin cifrar, C:H). T1190 por acceso sin privilegios a servicio remoto. T1041 (exfiltración) y T1557 (MITM) como impactos por exposición de datos cifrados incompletos.

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

Network SegmentationNetwork Intrusion PreventionLimit Access to Resource Over NetworkFilter Network TrafficVulnerability ScanningUser Training

Tecnologías afectadas (1)

Mozilla — Firefox

CWE

Referencias

JSON original (NVD)

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