CVE-2026-43126 ALSA: mixer: oss: Add card disconnect checkpoints
A use-after-free vulnerability in the Linux kernel ALSA OSS mixer allows attackers to potentially execute code or escalate privileges via race conditions during device disconnection.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-43126?
CVE-2026-43126 is a high-severity use after free vulnerability in Linux kernel, published on 6 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
ALSA: mixer: oss: Add card disconnect checkpoints
ALSA OSS mixer layer calls the kcontrol ops rather individually, and pending calls might be not always caught at disconnecting the device.
For avoiding the potential UAF scenarios, add sanity checks of the card disconnection at each entry point of OSS mixer accesses. The rwsem is taken just before that check, hence the rest context should be covered by that properly.
Which versions are affected by CVE-2026-43126?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-43126?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-43126 being exploited?
There is no known exploitation of CVE-2026-43126 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-43126, DEBIAN-CVE-2026-43126, GHSA-3m8w-q233-vhrp, ROOT-OS-DEBIAN-11-CVE-2026-43126, ROOT-OS-DEBIAN-12-CVE-2026-43126, ROOT-OS-UBUNTU-2204-CVE-2026-43126 and 2 more.