CVE-2026-53996 (GCVE-0-2026-53996)

Vulnerability from cvelistv5 – Published: 2026-08-12 12:42 – Updated: 2026-08-14 16:50
VLAI
Title
NetBSD hdaudio(4) Driver Privilege Bypass Use-After-Free via HDAUDIO_FGRP_SETCONFIG ioctl
Summary
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.
Severity
7.3 (High)
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
7 (High)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-12 15:24 UTC
CWE
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 7605 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
The NetBSD Foundation NetBSD Affected: 0 , ≤ 11 (custom)
    cpe:2.3:o:netbsd:netbsd:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-12 00:00
Credits
Nasm
Show details on NVD website
To clipboard 

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How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

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