Cloudanix VulnDB

CVE-2026-93184

None

CVSS

—

EPSS

0.2%

Published

Sep 17, 2026

CISA due date

—

Cloudanix analysis

Schedule a fix SSVC: Track

A bug in Linux audio hardware initialization can cause the system to freeze if certain audio settings are accessed too early.

Exploitation
Local Privilege
Attacker needs
Local User
Complexity
Low
Impact
Denial Of Service
Component
OS kernel
Class
Denial of service
Remediation
Upgrade
Effort
Medium
Patch risk
Low

What it actually does

The vulnerability allows register writes to target unpowered hardware in the AUDMIX block after pm_runtime_enable() but before the first runtime resume, resulting in a system hang.

Why it matters to the business

Systems using the fsl_audmix audio mixer may experience unexpected hangs or crashes during initialization, leading to downtime on affected Linux devices.

How an attack unfolds

An attacker with local access can trigger audio subsystem initialization paths such as DAPM or ALSA controls shortly after probe to cause writes to suspended hardware, resulting in a denial of service via system hang.

How to fix it

Apply the kernel patch that calls pm_runtime_resume_and_get() immediately after pm_runtime_enable() and handles PM-disabled cases by directly calling fsl_audmix_runtime_resume().

How to confirm the fix worked

Verify the presence of the updated pm_runtime handling code in the fsl_audmix probe function and test that register accesses succeed without hangs.

Typical attack path

  1. Gain local access to the system
  2. Trigger audio device probe or ALSA control access before runtime resume
  3. Cause register write to unpowered hardware
  4. Induce system hang

How to detect it

Look for kernel logs indicating hangs or oops related to fsl_audmix or AUDMIX register accesses during boot or audio init; check dmesg for PM related errors.

What your security team should do

  • Update to a kernel version containing the fix for this runtime PM issue
  • Monitor for audio subsystem related hangs on affected hardware
  • Test audio functionality after kernel updates

The record

In the Linux kernel, the following vulnerability has been resolved: ASoC: fsl_audmix: rework runtime PM handling in probe After pm_runtime_enable() the AUDMIX block is powered off and stays suspended until the first runtime resume. Register writes issued between probe() and the first resume (e.g. from DAPM or ALSA control paths) target unpowered hardware and cause a system hang. Fix this by calling pm_runtime_resume_and_get() immediately after pm_runtime_enable() to power the hardware up and enable its clocks. Release the reference afterwards with pm_runtime_put() to allow the runtime PM framework to suspend the device and switch the regmap to cache-only mode when idle. When CONFIG_PM is disabled or runtime PM is not enabled, pm_runtime_* calls are stubs that do not power up the hardware. Handle this case explicitly by calling fsl_audmix_runtime_resume() directly so the hardware is always initialised and its clocks are enabled, ensuring register accesses succeed regardless of PM configuration.

Affected packages

Ecosystem Package Introduced Fixed