CVE-2026-64603 platform/x86: intel-hid: Protect ACPI notify handler against recursion
A race condition in the Linux kernel intel-hid driver can cause a NULL pointer dereference and system crash when tablet mode events occur simultaneously on multiple CPUs.
- 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-2026-64603?
CVE-2026-64603 is a vulnerability in Linux, published on 6 Aug 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:
platform/x86: intel-hid: Protect ACPI notify handler against recursion
Since commit e2ffcda16290 ("ACPI: OSL: Allow Notify () handlers to run on all CPUs") ACPI notify handlers like the intel-hid notify_handler() may run on multiple CPU cores racing with themselves.
On convertibles and detachables (matched by DMI chassis-type 31 and 32 in dmi_auto_add_switch[]) the SW_TABLET_MODE input device is registered lazily from notify_handler() on the first tablet-mode event, via intel_hid_switches_setup(). When two such events race on different CPUs both can pass the !priv->switches check and register the priv->switches input device twice, resulting in a duplicate sysfs entry and a subsequent NULL pointer dereference.
This is the same class of bug fixed by commit e075c3b13a0a ("platform/x86: intel-vbtn: Protect ACPI notify handler against recursion") for the sibling intel-vbtn driver.
Protect intel-hid notify_handler() from racing with itself with a mutex to fix this.
Which versions are affected by CVE-2026-64603?
How do I fix CVE-2026-64603?
Apply the vendor's patch.
Is CVE-2026-64603 being exploited?
There is no known exploitation of CVE-2026-64603 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-64603, DEBIAN-CVE-2026-64603, GHSA-7vvj-68jr-4vwq, UBUNTU-CVE-2026-64603.