CVE-2025-38235: Linux kernel · HID: appletb-kbd: fix "appletb_backlight" backlight device reference counting
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium.
Data as of 13 Nov 2026, 18:29 UTC
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 6 Jul 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 13 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 24.04 LTSlinux-azure-6.11pkg:deb/ubuntu/linux-azure-6.11?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-gcp-6.11pkg:deb/ubuntu/linux-gcp-6.11?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-hwe-6.11pkg:deb/ubuntu/linux-hwe-6.11?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-lowlatency-hwe-6.11pkg:deb/ubuntu/linux-lowlatency-hwe-6.11?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-raspi-realtimepkg:deb/ubuntu/linux-raspi-realtime?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-realtimepkg:deb/ubuntu/linux-realtime?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
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.
References
- ubuntu.com/security/CVE-2025-38235 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-38235 (opens in a new tab)
- git.kernel.org/linus/4540e41e753a7d69ecd3f5bad51fe620205c3a18 (opens in a new tab)
- git.kernel.org/stable/c/4540e41e753a7d69ecd3f5bad51fe620205c3a18 (opens in a new tab)
- git.kernel.org/stable/c/751d5437112a3f387de4ef6d2d1c131068ff7627 (opens in a new tab)