---
id: CVE-2026-23089
title: 'ALSA: usb-audio: Fix use-after-free in snd_usb_mixer_free()'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  ALSA: usb-audio: Fix use-after-free in snd_usb_mixer_free()

  When snd_usb_create_mixer() fails, snd_usb_mixer_free() frees
  mixer->id_elems but the controls already adde…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 6639b6c2367f884ca172b78d69f7da17bfab2e5e <
    51b1aa6fe7dc87356ba58df06afb9677c9b841ea
  - >-
    Linux >= 6639b6c2367f884ca172b78d69f7da17bfab2e5e <
    56fb6efd5d04caf6f14994d51ec85393b9a896c6
  - >-
    Linux >= 6639b6c2367f884ca172b78d69f7da17bfab2e5e <
    7009daeefa945973a530b2f605fe445fc03747af
  - >-
    Linux >= 6639b6c2367f884ca172b78d69f7da17bfab2e5e <
    7bff0156d13f0ad9436e5178b979b063d59f572a
  - >-
    Linux >= 6639b6c2367f884ca172b78d69f7da17bfab2e5e <
    e6f103a22b08daf5df2f4aa158081840e5910963
  - >-
    Linux >= 6639b6c2367f884ca172b78d69f7da17bfab2e5e <
    dc1a5dd80af1ee1f29d8375b12dd7625f6294dad
  - >-
    Linux >= 6639b6c2367f884ca172b78d69f7da17bfab2e5e <
    930e69757b74c3ae083b0c3c7419bfe7f0edc7b2
  - Linux 2.6.13
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-06-10T20:40:33.270292Z'
published: '2026-02-04'
updated: '2026-10-19'
sourceUpdated: '2026-10-19T18:25:30.214Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-23089'
references:
  - url: 'https://git.kernel.org/stable/c/51b1aa6fe7dc87356ba58df06afb9677c9b841ea'
  - url: 'https://git.kernel.org/stable/c/56fb6efd5d04caf6f14994d51ec85393b9a896c6'
  - url: 'https://git.kernel.org/stable/c/7009daeefa945973a530b2f605fe445fc03747af'
  - url: 'https://git.kernel.org/stable/c/7bff0156d13f0ad9436e5178b979b063d59f572a'
  - url: 'https://git.kernel.org/stable/c/e6f103a22b08daf5df2f4aa158081840e5910963'
  - url: 'https://git.kernel.org/stable/c/dc1a5dd80af1ee1f29d8375b12dd7625f6294dad'
  - url: 'https://git.kernel.org/stable/c/930e69757b74c3ae083b0c3c7419bfe7f0edc7b2'
tags:
  - cve.org
epss: 0.00158
epssPercentile: 0.04495
ingestedAt: '2026-10-19T18:35:50.106Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

ALSA: usb-audio: Fix use-after-free in snd_usb_mixer_free()

When snd_usb_create_mixer() fails, snd_usb_mixer_free() frees
mixer->id_elems but the controls already added to the card still
reference the freed memory. Later when snd_card_register() runs,
the OSS mixer layer calls their callbacks and hits a use-after-free read.

Call trace:
  get_ctl_value+0x63f/0x820 sound/usb/mixer.c:411
  get_min_max_with_quirks.isra.0+0x240/0x1f40 sound/usb/mixer.c:1241
  mixer_ctl_feature_info+0x26b/0x490 sound/usb/mixer.c:1381
  snd_mixer_oss_build_test+0x174/0x3a0 sound/core/oss/mixer_oss.c:887
  ...
  snd_card_register+0x4ed/0x6d0 sound/core/init.c:923
  usb_audio_probe+0x5ef/0x2a90 sound/usb/card.c:1025

Fix by calling snd_ctl_remove() for all mixer controls before freeing
id_elems. We save the next pointer first because snd_ctl_remove()
frees the current element.

## Affected

- `Linux >= 6639b6c2367f884ca172b78d69f7da17bfab2e5e < 51b1aa6fe7dc87356ba58df06afb9677c9b841ea`
- `Linux >= 6639b6c2367f884ca172b78d69f7da17bfab2e5e < 56fb6efd5d04caf6f14994d51ec85393b9a896c6`
- `Linux >= 6639b6c2367f884ca172b78d69f7da17bfab2e5e < 7009daeefa945973a530b2f605fe445fc03747af`
- `Linux >= 6639b6c2367f884ca172b78d69f7da17bfab2e5e < 7bff0156d13f0ad9436e5178b979b063d59f572a`
- `Linux >= 6639b6c2367f884ca172b78d69f7da17bfab2e5e < e6f103a22b08daf5df2f4aa158081840e5910963`
- `Linux >= 6639b6c2367f884ca172b78d69f7da17bfab2e5e < dc1a5dd80af1ee1f29d8375b12dd7625f6294dad`
- `Linux >= 6639b6c2367f884ca172b78d69f7da17bfab2e5e < 930e69757b74c3ae083b0c3c7419bfe7f0edc7b2`
- `Linux 2.6.13`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.