CVE-2026-31751
In the Linux kernel, the following vulnerability has been resolved:
comedi: dt2815: add hardware detection to prevent crash
The dt2815 driver crashes when attached to I/O ports without actual hardware present. This occurs because syzkaller or users can attach the driver to arbitrary I/O addresses via COMEDI_DEVCONFIG ioctl.
When no hardware exists at the specified port, inb() operations return 0xff (floating bus), but outb() operations can trigger page faults due to undefined behavior, especially under race conditions:
Add hardware detection by reading the status register before attempting any write operations. If the read returns 0xff, assume no hardware is present and fail the attach with -ENODEV. This prevents crashes from outb() operations on non-existent hardware.
Detalles técnicos trazas, registros y código del informe original
BUG: unable to handle page fault for address: 000000007fffff90 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page RIP: 0010:dt2815_attach+0x6e0/0x1110
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 4.7
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.11%
- Percentil entre todas las CVEs puntuadas: 1
- 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).
Tecnologías afectadas (1)
CWE
- CWE-362
Referencias
- https://git.kernel.org/stable/c/0dcf33994b8dcf3db36530fb7e2cf9f89e5cbac3
- https://git.kernel.org/stable/c/34b13250c618d7441508c6ef369144aa8a9b9bfa
- https://git.kernel.org/stable/c/34c8b3a91bdfbe4573650b4cd750ef639101fdc5
- https://git.kernel.org/stable/c/65c528fbeddd88478c210052f6c7b21be4973156
- https://git.kernel.org/stable/c/8d63161837f1bf8810dbcd2a583c2bbf5ca6d733
- https://git.kernel.org/stable/c/93853512f565e625df2397f0d8050d6aafd7c3ad
- https://git.kernel.org/stable/c/d2a786efdb9971f2a647724625da5bbecc994dc9
- https://git.kernel.org/stable/c/d5d9df8b08d68d083ac57abc2c887dfb1f31af63
JSON original (NVD)
Mostrar
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