# CVE-2026-93115: platform/mellanox: mlxbf-pmc: Check ACPI_COMPANION() against NULL

> A local attacker with high privileges can force-bind a driver to a device lacking an ACPI companion, causing a kernel NULL pointer dereference and system crash.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 17 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-102006, BELL-CVE-2026-93115, DEBIAN-CVE-2026-93115, GHSA-hf49-hh29-x2wv, UBUNTU-CVE-2026-93115

## What is CVE-2026-93115?

CVE-2026-93115 is a vulnerability in Linux, published on 17 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:

platform/mellanox: mlxbf-pmc: Check ACPI_COMPANION() against NULL

Every platform driver can be forced to match a device that doesn't match
its list of device IDs because of device_match_driver_override(), so
platform drivers that rely on the existence of a device's ACPI companion
object need to verify its presence.

mlxbf_pmc_probe() passes the result of ACPI_COMPANION() to
acpi_device_hid(), which dereferences it, so force-binding the driver to
a device without an ACPI companion leads to a NULL pointer dereference.

Accordingly, add a requisite ACPI_COMPANION() check against NULL to the
mlxbf-pmc driver and return -ENODEV when the companion is missing.

## Which versions are affected by CVE-2026-93115?


## How do I fix CVE-2026-93115?

Apply the vendor's patch.

## Is CVE-2026-93115 being exploited?

There is no known exploitation of CVE-2026-93115 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-93115 and fix it if it is affected.

What it is: CVE-2026-93115 is a vulnerability in Linux, published on 17 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-2026-93115 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-2026-93115/ (Markdown: https://insights.sbomify.com/CVE-2026-93115/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-93115
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-93115
- OSV: https://osv.dev/vulnerability/CVE-2026-93115

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-93115/
Summaries are generated and may contain mistakes; the official description above is the record.