CVE-2025-38235: HID: appletb-kbd: fix "appletb_backlight" backlight device reference counting

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-07-06 · updated 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: HID: appletb-kbd: fix "appletb_backlight" backlight device reference counting During appletb_kbd_probe, probe attempts to get the backlight device by name. When this happens backlight_device_get_by_name looks for a device in the backlight class which has name "appletb_backlight" and upon finding a match it increments the reference count for the device and returns it to the caller. However this reference is never released leading to a reference leak. Fix this by decrementing the backlight device reference count on removal via put_device and on probe failure.

Affected products

Linux kernel: from 6.15 before 6.15.5; 6.16-rc1, 6.16-rc2, 6.16-rc3 — fixed in 6.15.5

How to fix

Upgrade to a fixed version: Linux kernel 6.15.5. Check the vendor advisory for mitigations.

References

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