CVE-2025-38685
Estado: ModificadaAlta (7.8)—
In the Linux kernel, the following vulnerability has been resolved:
fbdev: Fix vmalloc out-of-bounds write in fast_imageblit
This issue triggers when a userspace program does an ioctl FBIOPUT_CON2FBMAP by passing console number and frame buffer number. Ideally this maps console to frame buffer and updates the screen if console is visible.
As part of mapping it has to do resize of console according to frame buffer info. if this resize fails and returns from vc_do_resize() and continues further. At this point console and new frame buffer are mapped and sets display vars.
Leer descripción completaMostrar menos
Despite failure still it continue to proceed updating the screen at later stages where vc_data is related to previous frame buffer and frame buffer info and display vars are mapped to new frame buffer and eventully leading to out-of-bounds write in fast_imageblit(). This bheviour is excepted only when fg_console is equal to requested console which is a visible console and updates screen with invalid struct references in fbcon_putcs().
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: 0.18%
- Percentil entre todas las CVEs puntuadas: 7
- 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
T1068Exploitation for Privilege Escalationprivilege escalation85 % - Impacto principal
T1059Command and Scripting Interpreterexecution75 %
Vulnerabilidad local (AV:L, PR:L) que escala privilegios mediante un fallo en vc_do_resize() al mapear consola a framebuffer. El atacante logra ejecución de código arbitrario en el kernel vía out-of-bounds write en fast_imageblit().
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
- CWE-787
Referencias
- https://git.kernel.org/stable/c/078e62bffca4b7e72e8f3550eb063ab981c36c7a
- https://git.kernel.org/stable/c/27b118aebdd84161c8ff5ce49d9d536f2af10754
- https://git.kernel.org/stable/c/4c4d7ddaf1d43780b106bedc692679f965dc5a3a
- https://git.kernel.org/stable/c/56701bf9eeb63219e378cb7fcbd066ea4eaeeb50
- https://git.kernel.org/stable/c/af0db3c1f898144846d4c172531a199bb3ca375d
- https://git.kernel.org/stable/c/cfec17721265e72e50cc69c6004fe3475cd38df2
- https://git.kernel.org/stable/c/ed9b8e5016230868c8d813d9179523f729fec8c6
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
- https://cert-portal.siemens.com/productcert/html/ssa-032379.html
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html
JSON original (NVD)
Mostrar
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