# CVE-2026-98664: iio: imu: adis16400: fix unprotected debugfs reads

> A use-after-free vulnerability in the Linux kernel adis16400 driver allows local attackers to cause a denial of service or potentially execute code via unprotected debugfs reads.

- **Severity:** Not scored
- **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:** 18 Oct 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-109127, BELL-CVE-2026-98664, DEBIAN-CVE-2026-98664, GHSA-w4fg-xq8w-gq57, UBUNTU-CVE-2026-98664

## What is CVE-2026-98664?

CVE-2026-98664 is an use after free vulnerability in Linux, published on 18 Oct 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:

iio: imu: adis16400: fix unprotected debugfs reads

adis16400_serial_number_fops is open coded and never calls
debugfs_file_get(), so debugfs_remove_recursive() does not wait for a
read in progress and unbind frees the iio_dev underneath it.

Commit ae1d37a9bb4b ("iio: imu: adis16400: use DEFINE_DEBUGFS_ATTRIBUTE
instead of DEFINE_SIMPLE_ATTRIBUTE") converted product_id and
flash_count to DEFINE_DEBUGFS_ATTRIBUTE, which protects itself, but
moved all three files to debugfs_create_file_unsafe().

serial_number prints three registers as "%.4x-%.4x-%.4x" and
DEFINE_DEBUGFS_ATTRIBUTE() formats a single u64, so it cannot be
converted without changing what the file returns. adis16475 and
adis16550 already use debugfs_create_file() for their open coded
files. Use it here too.

## Which versions are affected by CVE-2026-98664?


## How do I fix CVE-2026-98664?

Apply the vendor's patch.

## Is CVE-2026-98664 being exploited?

There is no known exploitation of CVE-2026-98664 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-98664 and fix it if it is affected.

What it is: CVE-2026-98664 is an use after free vulnerability in Linux, published on 18 Oct 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-2026-98664 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-2026-98664/ (Markdown: https://insights.sbomify.com/CVE-2026-98664/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-98664
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-98664
- OSV: https://osv.dev/vulnerability/CVE-2026-98664

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-98664/
Summaries are generated and may contain mistakes; the official description above is the record.