CVE-2025-39964
Estado: AnalizadaMedia (5.5)⚠ Explotación activa
In the Linux kernel, the following vulnerability has been resolved:
crypto: af_alg - Disallow concurrent writes in af_alg_sendmsg
Issuing two writes to the same af_alg socket is bogus as the data will be interleaved in an unpredictable fashion. Furthermore, concurrent writes may create inconsistencies in the internal socket state.
Disallow this by adding a new ctx->write field that indiciates exclusive ownership for writing.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 5.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.28%
- Percentil entre todas las CVEs puntuadas: 69
- Fecha de la puntuación: 6/10/2026
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).
CISA KEV — explotada activamente
- Añadida al catálogo: 18/9/2026
- Plazo de remediación: 21/9/2026
- Uso conocido en ransomware: Unknown
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1068Exploitation for Privilege Escalationprivilege escalation85 % - Impacto principal
T1499.004Application or System Exploitationimpact75 %
AV:L PR:L sin interacción del usuario, afecta disponibilidad (DoS) por race condition en escrituras concurrentes al socket af_alg; escalada local mediante inconsistencia de estado.
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 (3)
CWE
- CWE-362
- CWE-362
Referencias
- https://git.kernel.org/stable/c/0f28c4adbc4a97437874c9b669fd7958a8c6d6ce
- https://git.kernel.org/stable/c/1b34cbbf4f011a121ef7b2d7d6e6920a036d5285
- https://git.kernel.org/stable/c/1f323a48e9b5ebfe6dc7d130fdf5c3c0e92a07c8
- https://git.kernel.org/stable/c/45bcf60fe49b37daab1acee57b27211ad1574042
- https://git.kernel.org/stable/c/7c4491b5644e3a3708f3dbd7591be0a570135b84
- https://git.kernel.org/stable/c/9aee87da5572b3a14075f501752e209801160d3d
- https://git.kernel.org/stable/c/e4c1ec11132ec466f7362a95f36a506ce4dc08c9
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-39964
JSON original (NVD)
Mostrar
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