# CVE-2026-31775: ALSA: ctxfi: Don't enumerate SPDIF1 at DAIO initialization

> A missing check in the ALSA ctxfi driver causes a kernel crash on specific hardware, leading to denial of service.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 1 May 2026
- **Updated:** 26 Oct 2026
- **Also known as:** BELL-CVE-2026-31775, DEBIAN-CVE-2026-31775, GHSA-h9h9-phrr-4q27, UBUNTU-CVE-2026-31775

## What is CVE-2026-31775?

CVE-2026-31775 is a medium-severity vulnerability in Linux kernel, published on 1 May 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:

ALSA: ctxfi: Don't enumerate SPDIF1 at DAIO initialization

The recent refactoring of xfi driver changed the assignment of
atc->daios[] at atc_get_resources(); now it loops over all enum
DAIOTYP entries while it looped formerly only a part of them.
The problem is that the last entry, SPDIF1, is a special type that
is used only for hw20k1 CTSB073X model (as a replacement of SPDIFIO),
and there is no corresponding definition for hw20k2.  Due to the lack
of the info, it caused a kernel crash on hw20k2, which was already
worked around by the commit b045ab3dff97 ("ALSA: ctxfi: Fix missing
SPDIFI1 index handling").

This patch addresses the root cause of the regression above properly,
simply by skipping the incorrect SPDIF1 type in the parser loop.

For making the change clearer, the code is slightly arranged, too.

## Which versions are affected by CVE-2026-31775?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-31775?

Apply the vendor's patch.

## Is CVE-2026-31775 being exploited?

There is no known exploitation of CVE-2026-31775 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-31775 and fix it if it is affected.

What it is: CVE-2026-31775 is a medium-severity vulnerability in Linux kernel, published on 1 May 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-2026-31775 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2026-31775/ (Markdown: https://insights.sbomify.com/CVE-2026-31775/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-31775
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-31775
- OSV: https://osv.dev/vulnerability/CVE-2026-31775

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-31775/
Summaries are generated and may contain mistakes; the official description above is the record.