NetBSD's hdaudio(4) driver in sys/dev/hdaudio/hdaudio.c contains a missing access control vulnerability that allows unprivileged local attackers to invoke the HDAUDIO_FGRP_SETCONFIG ioctl without elevated permissions by exploiting the absence of an access check on /dev/hdaudioN device nodes. Attackers can repeatedly issue HDAUDIO_FGRP_SETCONFIG from one thread while keeping DMA and IRQs live from a second thread to trigger a use-after-free race condition in hdafg_detach() between stream_stop() and stream_disestablish(), where a latched DMA interrupt dereferences a freed callback pointer, resulting in outcomes ranging from audio-subsystem denial of service and kernel panic to potential local kernel privilege escalation.
https://gnats.netbsd.org/60492
https://gist.github.com/n4sm/c9683ca728ecfada6c726f2a5afb50ed
https://cvsweb.NetBSD.org/bsdweb.cgi/src/sys/dev/hdaudio/hdaudio.c
Published: 2026-08-12
Updated: 2026-08-12
Base Score: 6
Vector: CVSS2#AV:L/AC:H/Au:S/C:C/I:C/A:C
Severity: Medium
Base Score: 7
Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity: High
Base Score: 7.3
Vector: CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Severity: High