CVE-2026-53996 PUBLISHED

NetBSD hdaudio(4) Driver Privilege Bypass Use-After-Free via HDAUDIO_FGRP_SETCONFIG ioctl

Assigner: VulnCheck
Reserved: 11.06.2026 Published: 12.08.2026 Updated: 12.08.2026

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.

Metrics

CVSS 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
CVSS Score: 7.3

Product Status

Vendor The NetBSD Foundation
Product NetBSD
Versions Default: affected
  • affected from 0 to 11 (incl.)

Credits

  • Nasm finder

References

Problem Types

  • Missing Authorization CWE