CVE-2026-90334 tty: clear cdev pointer after cdev_add() failure
A use-after-free in the Linux kernel tty subsystem allows local attackers to execute arbitrary code or escalate privileges.
- 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-2026-90334?
CVE-2026-90334 is an use after free vulnerability in Linux, published on 17 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:
tty: clear cdev pointer after cdev_add() failure
tty_cdev_add() drops the cdev reference when cdev_add() fails, but leaves driver->cdevs[index] pointing to freed memory. tty_unregister_device() later passes that stale pointer to cdev_del(), causing a use-after-free.
Clear the slot after dropping the reference.
Which versions are affected by CVE-2026-90334?
How do I fix CVE-2026-90334?
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-2026-90334 being exploited?
There is no known exploitation of CVE-2026-90334 in the wild and no public exploit code.
Sources
Also known as AZL-102474, BELL-CVE-2026-90334, DEBIAN-CVE-2026-90334, GHSA-346v-hcmm-349w, UBUNTU-CVE-2026-90334.