CVE-2026-89938 iio: chemical: atlas-sensor: use iio_trigger_poll_nested() to fix remove UAF
A use-after-free in the Linux kernel Atlas sensor driver allows attackers to execute arbitrary code or escalate privileges via race conditions during device removal.
- 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-2026-89938?
CVE-2026-89938 is a high-severity 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:
iio: chemical: atlas-sensor: use iio_trigger_poll_nested() to fix remove UAF
The atlas driver requests its hardware data-ready IRQ with devm_request_threaded_irq(); its threaded handler queues an irq_work, atlas_work_handler(), that calls iio_trigger_poll(data->trig).
The IRQ is devm-managed, so free_irq() runs from the devres unwind after atlas_remove() returns without flushing that irq_work. Once a buffer is enabled, conversion-complete IRQs keep firing and queueing it; a pending irq_work can therefore run after the unwind has freed atlas_data/indio_dev and the trigger, when atlas_work_handler() derives the atlas_data pointer via container_of() and dereferences data->trig, a use-after-free.
Call iio_trigger_poll_nested() directly from the threaded handler instead of bouncing through irq_work. free_irq() then drains the threaded handler, closing the window; other iio drivers with a threaded data-ready IRQ do the same (e.g. bmi270).
This issue was found by an in-house static analysis tool.
Which versions are affected by CVE-2026-89938?
How do I fix CVE-2026-89938?
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-2026-89938 being exploited?
There is no known exploitation of CVE-2026-89938 in the wild and no public exploit code.
Sources
Also known as AZL-101132, BELL-CVE-2026-89938, DEBIAN-CVE-2026-89938, GHSA-cv98-fww9-9mfg, UBUNTU-CVE-2026-89938.