# CVE-2026-97423: cxl/region: Validate partition index before array access

> An out-of-bounds array access in the Linux kernel CXL region driver can cause a system crash when the partition index is invalid.

- **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:** 25 Sep 2026
- **Also known as:** AZL-103835, BELL-CVE-2026-97423, DEBIAN-CVE-2026-97423, GHSA-c7p2-9jv2-f7w3, UBUNTU-CVE-2026-97423

## What is CVE-2026-97423?

CVE-2026-97423 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:

cxl/region: Validate partition index before array access

construct_region() reads cxled->part and uses it to index
cxlds->part[] without checking for a negative value. If the
partition was never resolved, part remains at its initial value
of -1, causing an out-of-bounds array access.

Add a guard to return -EBUSY when part is negative.

The check was dropped during a merge.

## Which versions are affected by CVE-2026-97423?


## How do I fix CVE-2026-97423?

Apply the vendor's patch.

## Is CVE-2026-97423 being exploited?

There is no known exploitation of CVE-2026-97423 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-97423 and fix it if it is affected.

What it is: CVE-2026-97423 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-2026-97423 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-2026-97423/ (Markdown: https://insights.sbomify.com/CVE-2026-97423/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-97423
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-97423
- OSV: https://osv.dev/vulnerability/CVE-2026-97423

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-97423/
Summaries are generated and may contain mistakes; the official description above is the record.