CVE-2026-89895 media: cobalt: Avoid freeing ALSA private data twice
A double-free vulnerability in the Linux kernel cobalt media driver allows local attackers to cause a denial of service or potentially execute arbitrary code.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-89895?
CVE-2026-89895 is an use after free vulnerability in Linux, published on 16 Sep 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:
media: cobalt: Avoid freeing ALSA private data twice
snd_cobalt_card_create() stores cobsc in sc->private_data and installs snd_cobalt_card_private_free() as sc->private_free. From that point, snd_card_free(sc) releases cobsc through the ALSA card cleanup path.
If cobalt_alsa_init() fails after snd_cobalt_card_create(), the err_exit_free path calls snd_card_free(sc) and then kfree(cobsc). That second free releases the same object again.
Remove the explicit kfree(cobsc) and leave ownership with the ALSA card.
This issue was found by a static analysis checker and confirmed by manual source review.
Which versions are affected by CVE-2026-89895?
How do I fix CVE-2026-89895?
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-2026-89895 being exploited?
There is no known exploitation of CVE-2026-89895 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-89895, DEBIAN-CVE-2026-89895, GHSA-r63g-3mcq-69jv, UBUNTU-CVE-2026-89895.