---
id: CVE-2026-89736
title: >-
  kernel: usb: gadget: u_audio: Fix use-after-free on sound card disconnect
  (CVE-2026-89736)
summary: >-
  A flaw was found in the Linux kernel's USB audio gadget driver (u_audio). This
  vulnerability occurs during sound card disconnection when Asynchronous Linux
  Sound Architecture (ALSA) control elements (kctls) remain open in userspace. A
  loca…
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
cwe: CWE-825
vendor: Red Hat
product: Linux
affected:
  - >-
    Linux >= 33f341c1fc60e172a3515c51bdabee11e83d1ee9 <
    a7ecd1a04f4f485d7be6443d0f0b2c61a800cb82
  - >-
    Linux >= b131989797f7287d7fdadb2bababc05a15d44750 <
    f983793f03148b097977f200298db215cd2d4438
  - >-
    Linux >= 3bc7324e4911351e39c54a62e6ca46321cb10faf <
    6f46762196f04464e1050a9ee94e72b917db9010
  - >-
    Linux >= 6c67ed9ad9b83e453e808f9b31a931a20a25629b <
    891a8d11f4d5eb50b2ce7570f4f98204a7a57493
  - >-
    Linux >= 6c67ed9ad9b83e453e808f9b31a931a20a25629b <
    c74ff0b1a0fca53d3ac185873c87d6a719b30a47
  - >-
    Linux >= 6c67ed9ad9b83e453e808f9b31a931a20a25629b <
    4e747c864a88537e18b1ffc19a1954c9686bb8e1
  - >-
    Linux >= 6c67ed9ad9b83e453e808f9b31a931a20a25629b <
    79a92896e2bb9471550c56fc23d8d93592f04c27
  - >-
    Linux >= 6c67ed9ad9b83e453e808f9b31a931a20a25629b <
    858965947081d10d41d9a1010a540d3d5eea958b
  - Linux 3e016ef2e72da93a2ea7afbb45de1b481b44d761
  - Linux 3256e152b645fc1e788ba44c2d8ced690113e3e6
  - Linux 0eda2004f38d95ef5715d62be884cd344260535b
  - Linux 43ca70753dfffd517d2af126da28690f8f615605
  - Linux >= 5.10.177 < 5.10.270
  - Linux >= 5.15.105 < 5.15.221
  - Linux >= 6.1.22 < 6.1.188
  - Linux >= 4.14.312 < 4.15
  - Linux >= 4.19.280 < 4.20
  - Linux >= 5.4.240 < 5.5
  - Linux >= 6.2.9 < 6.3
  - Linux 6.3
published: '2026-09-11'
updated: '2026-09-21'
sourceUpdated: '2026-09-21T17:28:09+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89736.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89736.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-89736'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532311'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-89736'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89736'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-89736.mbox
  - url: 'https://git.kernel.org/stable/c/a7ecd1a04f4f485d7be6443d0f0b2c61a800cb82'
  - url: 'https://git.kernel.org/stable/c/f983793f03148b097977f200298db215cd2d4438'
  - url: 'https://git.kernel.org/stable/c/6f46762196f04464e1050a9ee94e72b917db9010'
  - url: 'https://git.kernel.org/stable/c/891a8d11f4d5eb50b2ce7570f4f98204a7a57493'
  - url: 'https://git.kernel.org/stable/c/c74ff0b1a0fca53d3ac185873c87d6a719b30a47'
  - url: 'https://git.kernel.org/stable/c/4e747c864a88537e18b1ffc19a1954c9686bb8e1'
  - url: 'https://git.kernel.org/stable/c/79a92896e2bb9471550c56fc23d8d93592f04c27'
  - url: 'https://git.kernel.org/stable/c/858965947081d10d41d9a1010a540d3d5eea958b'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
  - score-dispute
epss: 0.00126
epssPercentile: 0.02628
scores:
  vendor: 5.5
  cna: 7.8
ingestedAt: '2026-09-14T15:23:07.449Z'
---

## Overview

A flaw was found in the Linux kernel's USB audio gadget driver (u_audio). This vulnerability occurs during sound card disconnection when Asynchronous Linux Sound Architecture (ALSA) control elements (kctls) remain open in userspace. A local attacker can exploit this timing issue by interacting with these kctls, leading to a use-after-free memory corruption. This could potentially result in arbitrary code execution or a denial of service.

## Vendor advisories

- **Red Hat VEX** · Moderate · updated 2026-09-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-89736.json)

**kernel: usb: gadget: u_audio: Fix use-after-free on sound card disconnect** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-21.

Not affected:

- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4

## Remediation

Refer to the advisory for fix availability.