# CVE-2026-90208: clocksource/drivers/samsung_pwm: Switch to raw_spinlock_t type

> A race condition in the Samsung PWM driver under PREEMPT_RT can cause a system crash when accessed from interrupt context.

- **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:** 17 Sep 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-103020, BELL-CVE-2026-90208, DEBIAN-CVE-2026-90208, GHSA-64fq-hj58-5rjq, UBUNTU-CVE-2026-90208

## What is CVE-2026-90208?

CVE-2026-90208 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:

clocksource/drivers/samsung_pwm: Switch to raw_spinlock_t type

Samsung PWM timer might be used as a clock source on some legacy systems.
When PREEMPT_RT is enabled on ARM, regular spinlock is converted to a
sleeping lock (mutex-based), which must not be used in atomic context
such as hard interrupt handlers. Switch the samsung_pwm_lock to the
raw_spinlock, which remains a true non-sleeping spinlock even
under PREEMPT_RT.

## Which versions are affected by CVE-2026-90208?


## How do I fix CVE-2026-90208?

Apply the vendor's patch.

## Is CVE-2026-90208 being exploited?

There is no known exploitation of CVE-2026-90208 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-90208 and fix it if it is affected.

What it is: CVE-2026-90208 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-2026-90208 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-2026-90208/ (Markdown: https://insights.sbomify.com/CVE-2026-90208/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-90208
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-90208
- OSV: https://osv.dev/vulnerability/CVE-2026-90208

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-90208/
Summaries are generated and may contain mistakes; the official description above is the record.