CVE-2025-1933
On 64-bit CPUs, when the JIT compiles WASM i32 return values they can pick up bits from left over memory. This can potentially cause them to be treated as a different type. This vulnerability was fixed in Firefox 136, Firefox ESR 115.21, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H
- Puntuación base: 7.6
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.32%
- Percentil entre todas las CVEs puntuadas: 23
- 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
T1203Exploitation for Client Executionexecution85 % - Impacto principal
T1005Data from Local Systemcollection75 % - Impacto secundario
T1059Command and Scripting Interpreterexecution65 %
UI:R + acceso remoto → T1203 (cliente). WASM JIT puede leer memoria (T1005) y potencialmente ejecutar código arbitrario (T1059) al manipular tipos.
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
- NVD-CWE-noinfo
Referencias
- https://bugzilla.mozilla.org/show_bug.cgi?id=1946004
- https://www.mozilla.org/security/advisories/mfsa2025-14/
- https://www.mozilla.org/security/advisories/mfsa2025-15/
- https://www.mozilla.org/security/advisories/mfsa2025-16/
- https://www.mozilla.org/security/advisories/mfsa2025-17/
- https://www.mozilla.org/security/advisories/mfsa2025-18/
- https://lists.debian.org/debian-lts-announce/2025/03/msg00006.html
JSON original (NVD)
Mostrar
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