CVE-2026-52993

Estado: ModificadaCrítica (9.8)—

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

tipc: fix double-free in tipc_buf_append()

tipc_msg_validate() can potentially reallocate the skb it is validating, freeing the old one. In tipc_buf_append(), it was being called with a pointer to a local variable which was a copy of the caller's skb pointer.

If the skb was reallocated and validation subsequently failed, the error handling path would free the original skb pointer, which had already been freed, leading to double-free.

Fix this by checking if head now points to a newly allocated reassembled skb. If it does, reassign *headbuf for later freeing operations.

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Puntuación base: 9.8

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.40%
Percentil entre todas las CVEs puntuadas: 32
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.

ExplotaciónT1190 Exploit Public-Facing Applicationinitial access75 %
Impacto secundarioT1499.004 Application or System Exploitationimpact70 %

AV:N/AC:L/PR:N permite explotación remota sin privilegios (T1190). Double-free en kernel puede permitir ejecución de código o crash de servicio. CVSS crítico (C:H/I:H/A:H) sugiere ambos impactos.

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

Filter Network Traffic Vulnerability Scanning Privileged Account Management Network Segmentation Limit Access to Resource Over Network Application Isolation and Sandboxing

Tecnologías afectadas (1)

Linux — Linux Kernel

CWE

CWE-415
CWE-763

Referencias

JSON original (NVD)

Mostrar

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