---
cve: "CVE-2026-53996"
severity: "HIGH"
cvss: 7.3
epss: "0.1%"
vendor: "The NetBSD Foundation"
kev: false
exploited: false
published: "2026-08-12 13:17:22"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-10-04T04:44:08+02:00"
---

# CVE-2026-53996

> 7.3 HIGH · 🧪 PoC

## Beschreibung

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.

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **none**
  - Automatable: **no**
  - Technical Impact: **total**

## CVSS-Vektor

```
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
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Lokal | good |
| AC Komplexität | Hoch | good |
| PR Privilegien | Gering | warn |
| UI Interaktion | Keine | bad |

## BSI-Hinweise (deutsch)

- [NetBSD Foundation NetBSD OS (hdaudio): Schwachstelle ermöglicht Erlangen von Administratorrechten und DoS](https://wid.cert-bund.de/portal/wid/sicherheitshinweis/WID-SEC-W-2026-2821) — _BSI-Einstufung: mittel_
  Ein lokaler Angreifer kann eine Schwachstelle in NetBSD Foundation NetBSD OS ausnutzen, um Administratorrechte zu erlangen und um einen Denial-of-Service-Zustand zu verursachen.

## Referenzen

- <https://gist.github.com/n4sm/c9683ca728ecfada6c726f2a5afb50ed>
- <https://gnats.netbsd.org/60492>
- <https://cvsweb.NetBSD.org/bsdweb.cgi/src/sys/dev/hdaudio/hdaudio.c>
- <https://www.vulncheck.com/advisories/netbsd-hdaudio-4-driver-privilege-bypass-use-after-free-via-hdaudio-fgrp-setconfig-ioctl>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-53996) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_