CVE-2026-46202

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

HID: appletb-kbd: run inactivity autodim from workqueues

The autodim code in hid-appletb-kbd takes backlight_device->ops_lock

via backlight_device_set_brightness() -> mutex_lock() from two

different atomic contexts:

* appletb_inactivity_timer() is a struct timer_list callback, so it

runs in softirq context. Every expiry triggers

BUG: sleeping function called from invalid context at kernel/locking/mutex.c:591

Call Trace:

<IRQ>

__might_resched

__mutex_lock

backlight_device_set_brightness

appletb_inactivity_timer

call_timer_fn

run_timer_softirq

* reset_inactivity_timer() is called from appletb_kbd_hid_event() and

appletb_kbd_inp_event(). On real USB hardware these run in

softirq/IRQ context (URB completion and input-event dispatch).

When the Touch Bar has already been dimmed or turned off, the

reset path calls backlight_device_set_brightness() dir

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References