# CVE-2026-64500: iio: adc: lpc32xx: Initialize completion before requesting IRQ

> A race condition in the LPC32xx ADC driver causes a kernel panic via null pointer dereference if an interrupt occurs before completion initialization.

- **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:** 25 Jul 2026
- **Updated:** 17 Aug 2026
- **Also known as:** BELL-CVE-2026-64500, DEBIAN-CVE-2026-64500, GHSA-h726-jm24-wvqc, ROOT-OS-UBUNTU-2204-CVE-2026-64500, UBUNTU-CVE-2026-64500

## What is CVE-2026-64500?

CVE-2026-64500 is a vulnerability in Linux, published on 25 Jul 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: adc: lpc32xx: Initialize completion before requesting IRQ

In the report from Jaeyoung Chung:

"lpc32xx_adc_probe() in drivers/iio/adc/lpc32xx_adc.c registers its
interrupt handler with devm_request_irq() before it initializes
st->completion with init_completion(). If an interrupt arrives after
devm_request_irq() and before init_completion(), the handler calls
complete() on an uninitialized completion, causing a kernel panic.

The probe path, in lpc32xx_adc_probe():

    iodev = devm_iio_device_alloc(&pdev->dev, sizeof(*st)); /* st kzalloc-zeroed */
    ...
    retval = devm_request_irq(&pdev->dev, irq, lpc32xx_adc_isr, 0,
                              LPC32XXAD_NAME, st);           /* register handler */
    ...
    init_completion(&st->completion);                       /* initialize completion */

lpc32xx_adc_isr() calls complete():

    complete(&st->completion);

If the device raises an interrupt before init_completion() runs,
complete() acquires the uninitialized wait.lock and walks the zeroed
task_list in swake_up_locked(). The zeroed task_list makes list_empty()
return false, so swake_up_locked() dereferences a NULL list entry,
triggering a KASAN wild-memory-access."

Fix the chance of a spurious IRQ causing an uninitialized pointer
dereference by moving init_completion() above devm_request_irq().

## Which versions are affected by CVE-2026-64500?


## How do I fix CVE-2026-64500?

Apply the vendor's patch.

## Is CVE-2026-64500 being exploited?

There is no known exploitation of CVE-2026-64500 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-64500 and fix it if it is affected.

What it is: CVE-2026-64500 is a vulnerability in Linux, published on 25 Jul 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-2026-64500 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-2026-64500/ (Markdown: https://insights.sbomify.com/CVE-2026-64500/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64500
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64500
- OSV: https://osv.dev/vulnerability/CVE-2026-64500

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64500/
Summaries are generated and may contain mistakes; the official description above is the record.