# 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.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 6 Aug 2026
- **Updated:** 17 Aug 2026
- **Also known as:** BELL-CVE-2026-64603, DEBIAN-CVE-2026-64603, GHSA-7vvj-68jr-4vwq, UBUNTU-CVE-2026-64603

## 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.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-64603 and fix it if it is affected.

What it is: 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.
Exploitation: There is no known exploitation of CVE-2026-64603 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-64603/ (Markdown: https://insights.sbomify.com/CVE-2026-64603/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64603
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64603
- OSV: https://osv.dev/vulnerability/CVE-2026-64603

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64603/
Summaries are generated and may contain mistakes; the official description above is the record.