# CVE-2026-68434: serial: 8250_mid: Fix NULL function pointer dereference on DNV/ICX-D/SNR platforms

> A NULL pointer dereference in the Linux kernel serial driver causes a system crash on specific Intel platforms, requiring a kernel patch.

- **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:** 12 Aug 2026
- **Updated:** 23 Aug 2026
- **Also known as:** BELL-CVE-2026-68434, DEBIAN-CVE-2026-68434, GHSA-97r7-mpr3-66vh, UBUNTU-CVE-2026-68434

## What is CVE-2026-68434?

CVE-2026-68434 is a vulnerability in Linux, published on 12 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:

serial: 8250_mid: Fix NULL function pointer dereference on DNV/ICX-D/SNR platforms

Commit b1b4efea05a5 ("serial: 8250_mid: Disable DMA for selected
platforms") replaced the dnv_board setup and exit callbacks with
PTR_IF(false, ...), which evaluates to NULL. However, the three call
sites in mid8250_probe() and mid8250_remove() unconditionally
dereference these function pointers without NULL checks, causing a NULL
pointer dereference (kernel oops) on any Denverton (DNV), Ice Lake Xeon
D (ICX-D/CDF), or Snowridge (SNR) platform.

Fix this by adding the missing NULL checks before calling the setup and
exit callbacks.

## Which versions are affected by CVE-2026-68434?


## How do I fix CVE-2026-68434?

Apply the vendor's patch.

## Is CVE-2026-68434 being exploited?

There is no known exploitation of CVE-2026-68434 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-68434 and fix it if it is affected.

What it is: CVE-2026-68434 is a vulnerability in Linux, published on 12 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-2026-68434 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-2026-68434/ (Markdown: https://insights.sbomify.com/CVE-2026-68434/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-68434
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-68434
- OSV: https://osv.dev/vulnerability/CVE-2026-68434

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-68434/
Summaries are generated and may contain mistakes; the official description above is the record.