# CVE-2026-97446: ACPICA: Fix NULL pointer dereference in acpi_ns_custom_package()

> A NULL pointer dereference in the Linux kernel's ACPICA component allows a local attacker to cause a system crash via malicious firmware.

- **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:** 24 Sep 2026
- **Updated:** 3 Oct 2026
- **Also known as:** AZL-103985, BELL-CVE-2026-97446, DEBIAN-CVE-2026-97446, GHSA-hqv9-j885-c7xr, UBUNTU-CVE-2026-97446

## What is CVE-2026-97446?

CVE-2026-97446 is a vulnerability in Linux, published on 24 Sep 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:

ACPICA: Fix NULL pointer dereference in acpi_ns_custom_package()

acpi_ns_custom_package() unconditionally dereferences the first element
of the package to read the _BIX version number, without checking for
NULL:

    if ((*Elements)->Common.Type != ACPI_TYPE_INTEGER)

When firmware returns a _BIX package whose first element is an
unresolvable reference, ACPICA evaluates that entry to NULL.
acpi_ns_remove_null_elements() does not strip NULL entries for
ACPI_PTYPE_CUSTOM packages (fixed-position format would break if
elements were shifted), so acpi_ns_custom_package() sees the NULL
and causes a crash.

Add a NULL check for the first element (version field) before
dereferencing it. The caller then receives AE_AML_OPERAND_TYPE
instead of crashing.

## Which versions are affected by CVE-2026-97446?


## How do I fix CVE-2026-97446?

Apply the vendor's patch.

## Is CVE-2026-97446 being exploited?

There is no known exploitation of CVE-2026-97446 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-97446 and fix it if it is affected.

What it is: CVE-2026-97446 is a vulnerability in Linux, published on 24 Sep 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-2026-97446 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-2026-97446/ (Markdown: https://insights.sbomify.com/CVE-2026-97446/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-97446
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-97446
- OSV: https://osv.dev/vulnerability/CVE-2026-97446

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-97446/
Summaries are generated and may contain mistakes; the official description above is the record.