CVE-2024-56638

Estado: AnalizadaAlta (7.8)—

In the Linux kernel, the following vulnerability has been resolved:

netfilter: nft_inner: incorrect percpu area handling under softirq

Softirq can interrupt ongoing packet from process context that is walking over the percpu area that contains inner header offsets.

Disable bh and perform three checks before restoring the percpu inner header offsets to validate that the percpu area is valid for this skbuff:

3) Finally, validate if the percpu area refers to this tunnel type.

Only after these three checks the percpu area is restored to a on-stack copy and bh is enabled again.

After inner header fetching, the on-stack copy is stored back to the percpu area.

Detalles técnicos trazas, registros y código del informe original

1) If the NFT_PKTINFO_INNER_FULL flag is set on, then this skbuff
   has already been parsed before for inner header fetching to
   register.

2) Validate that the percpu area refers to this skbuff using the
   skbuff pointer as a cookie. If there is a cookie mismatch, then
   this skbuff needs to be parsed again.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 7.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.23%
Percentil entre todas las CVEs puntuadas: 12
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.

ExplotaciónT1068 Exploitation for Privilege Escalationprivilege escalation85 %
Impacto principalT1499.004 Application or System Exploitationimpact75 %
Impacto secundarioT1565.001 Stored Data Manipulationimpact60 %

AV:L/PR:L sin UI indica escalada local. El desbordamiento de percpu en softirq puede provocar DoS (interrupción de paquetes) o corrupción de datos de red bajo condiciones de race condition.

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

Threat Intelligence Program Restrict File and Directory Permissions Remote Data Storage Filter Network Traffic Execution Prevention Encrypt Sensitive Information

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

NVD-CWE-noinfo

Referencias

JSON original (NVD)

Mostrar

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