CVE-2026-98116

A flaw was found in the Linux kernel's ALSA (Advanced Linux Sound Architecture) sound subsystem. A race condition between concurrent memory mapping operations and audio buffer reallocations allows memory pages to be released while still mapped as writable. A local user can exploit this vulnerability to trigger a use-after-free condition, potentially resulting in local privilege escalation or a denial of service.

This vulnerability is rated as an Important severity impact because an unprivileged local user with access to sound devices can leverage kernel memory corruption to escalate privileges to root, rather than causing merely a temporary denial of service. In typical Red Hat Enterprise Linux server deployments, physical audio controllers are rarely present and access to sound device nodes is not exposed to remote or unauthenticated sessions. Systems configured with desktop environments or virtual machines exposing emulated sound hardware permit local users to interact directly with PCM devices, which enables the vulnerable path.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

To mitigate this vulnerability on systems where audio capabilities are not required, disable the ALSA PCM kernel module (snd-pcm).

1. Prevent the module from loading by creating a modprobe configuration file:

echo "install snd-pcm /bin/true" > /etc/modprobe.d/disable-snd-pcm.conf

2. If the module is currently loaded, unload it:

modprobe -r snd-pcm

Caveats: Disabling this module prevents audio hardware, playback, and recording from operating.

Warning: Unloading the module will interrupt active audio processes. If the module is currently in use and cannot be unloaded, a system restart is required for the configuration to take effect.