CVE-2026-31539
In the Linux kernel, the following vulnerability has been resolved:
smb: smbdirect: introduce smbdirect_socket.recv_io.credits.available
The logic off managing recv credits by counting posted recv_io and granted credits is racy.
That's because the peer might already consumed a credit, but between receiving the incoming recv at the hardware and processing the completion in the 'recv_done' functions we likely have a window where we grant credits, which don't really exist.
So we better have a decicated counter for the available credits, which will be incremented when we posted new recv buffers and drained when we grant the credits to the peer.
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: 0.43%
- Percentil entre todas las CVEs puntuadas: 35
- 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).
🎯 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 access45 % - Impacto principal
T1499.004Application or System Exploitationimpact75 %
Vector CVSS N/N/N indica acceso remoto sin autenticación. La vulnerabilidad de race condition en créditos SMB Dircet permite agotamiento de recursos de recepción, causando DoS de aplicación remota (T1499.004). La pista refuerza explotación T1190 y impacto DoS.
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 (1)
CWE
- NVD-CWE-noinfo
Referencias
JSON original (NVD)
Mostrar
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